transmission network design and architecture guidelines version 1 3
TRANSCRIPT
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
1/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 1 of 64
Reference: Transmission network design & architecture guidelines
Version: 1.3 Draft
Date: 10 June 2013
Author(s): David Powders
Filed As:
Status: Draft Version (1.3)
ApprovedBy:
Signature /Date:
.......................................................... / ......................
NSI Ireland
Transmission NetworkDesign & Architecture
Guidelines
Version 1.3 Draft
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
2/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 2 of 64
Document HistoryVersion Date Comment
1.0 Draft 27.01.2013 First draft
1.1 Draft 25.02.2013 Incorporating changes requested from parentoperators;- Resilience- Routing- Performance monitoring
1.2 Draft 14.05.2013 - Updated BT TT Routing section 2.3
1.3 Draft 10.06.2013 - Section 2.3 E-Lines added to TT design- Section 2.6 Updated dimensioning rules- Section 2.6.4 Updated Policing allocation per class- Section 3.x added (Site design)
Reference documents1 (2012.12.27) OPTIMA BLUEPRINT V1.0 DRAFT FINAL.doc
2 Total Transmission IP design - DLD V2 2 (2)[1].pdf
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
3/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 3 of 64
Contents
DOCUMENT HISTORY ....................................................................................................... ................ 2REFERENCE DOCUMENTS......................................................................... ...................................... 21.0 INTRODUCTION.............................................................................................. ........................... 5
1.1 BACKGROUND............................................................................................................................. 51.2 SCOPE OF DOCUMENT................................................................. ................................................. 51.3 DOCUMENT STRUCTURE.............................................................. ................................................ 5
2.0 PROPOSED NETWORK ARCHITECTURE ............................................................... ................ 62.1TRANSMISSION NETWORK............................................................... ................................................ 72.1DATA CENTRE SOLUTION................................................................ ................................................ 8
2.1.1 Physical interconnection ........................................................ ................................................ 82.2SELF BUILD BACKHAUL NETWORK............................................................ ...................................... 9
2.3.1 Self build fibre diversity ....................................................................................................... 122.3MANAGED BACKHAUL .................................................................................................................. 13
2.3.1 TT Network contract ........................................ .............................................................. ...... 132.3.3 Backhaul network selection.............................. ................................................................. ... 16
2.4 BACKHAUL ROUTING ................................................................................................................ 162.4.1 Legacy mobile services .................................... .............................................................. ...... 162.4.2 Enterprise services ................................................................. .................................... 172.4.3 IP services ......................................................... ......................................................... 17
2.4.3.1 L3VPN structure ............................................................................................................... 172.4.3.2 IP service Resilience........................................................................................................ 19
2.5 ACCESS MICROWAVE NETWORK........................................................... .................................... 202.5.1 Baseband switching ................................................................................................ ... 212.5.2 Microwave DCN .......................................................... .............................................. 222.5.3 Backhaul Interconnections ................................................................ ......................... 22
2.6 NETWORK TOPOLOGY & TRAFFIC ENGINEERING ......................................................... .............. 232.6.1 Access Microwave topology & dimensioning ......................................................... ... 242.6.2 Access MW Resilience rules .............................................................. ......................... 272.6.3 Backhaul & Core transmission network dimensioning rules ..................................... 282.6.4 Traffic engineering .................................................................................................... 29
2.7 NETWORK SYNCHRONISATION .............................................................. .................................... 352.7.1 Self Built Transmission network ................................................................................ 362.7.2 Ethernet Managed services ............................................................... ......................... 372.7.3 DWDM network ........................................................... .............................................. 382.7.4 Mobile network clock recovery ......................................................... ......................... 39
2.7.4.1 Legacy Ran nodes ........................................................................................................... 392.7.4.2 Ericsson SRAN 2G ....................................................................................................... 392.7.4.3 Ericsson SRAN 3G & LTE ........................................................................................... 392.7.4.4 NSN 3G .......................................................................................................................... 402.8 DATA COMMUNICATIONSNETWORK(DCN) .............................................................. .............. 40
2.8.1 NSN 3G RAN Control Plane routing ......................................................................... 412.8.2 NSN 3G RAN O&M routing .............................................................. ......................... 41
2.9 TRANSMISSION NETWORK PERFORMANCE MONITORING ........................................................ ... 433.0 SITE CONFIGURATION ............................................................ .............................................. 45
3.1 CORE SITES ............................................................................................................................... 453.2 BACKHAUL SITES ...................................................................................................................... 51
3.2.1 BT TT locations ........................................................... ......................................................... 563.3ACCESS LOCATIONS ...................................................................................................................... 57
3.3.1 Access sites (Portacabin installation) .......................................................... .............. 573.3.2 Access site (Outdoor cabinet installation) .............................................................. ... 60
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
4/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 4 of 64
Figures
Figure 1 Proposed NSI transmission solution .................... ...................... ...................... ...................... ..................... . 7Figure 2 Example data centre northbound physical interconnect .................... ...................... ...................... ............... 8Figure 3 - Dublin Dark fibre IP/MPLS network ....................... ...................... ...................... ...................... ............. 10Figure 4 - National North East area IP/MPLS microwave network .................... ...................... ...................... ......... 11Figure 5aBT Total Transmission network............................................................................................................ 14Figure 5bNSI logical and physical transmission across the BT network ..................................... ...................... .. 15Figure 7Access Microwave topology ...................... ...................... ..................... ...................... ...................... ...... 21Figure 8Example VSI grouping configuration ...................... ...................... ...................... ...................... ............. 23Figure 10IP/MPLS traffic engineering .................... ...................... ...................... ..................... ...................... ...... 30Figure 11Enterprise traffic engineering ............................................................................................................... 31Figure 12Downlink traffic control mechanism ..................... ...................... ...................... ...................... ............. 32Figure 13- Normal link operation ............................................................................................................................ 34Figure 14
Self built synchronisation distribution ................... ...................... ...................... ...................... ............. 37
Figure 151588v2 distribution over Ethernet Managed service .................... ...................... ...................... ............. 38
Tables
Table 1: Self build fibre diversity ................... ...................... ...................... ...................... ......... 12Table 2: TT Access fibre diversity ..................... ..................... ...................... ...................... ...... 13Table 3 List of L3VPNs required......................................................................................... 18Table 4 Radio configuration V air interface bandwidth ..................................................... 25Table 5: Feeder link reference .................... ...................... ...................... ...................... ............. 26Table 6: CIR per technology reference...................................................................................... 26Table 5 Sample Quality of Service mapping...................................................................... 30Table 6 City Area (Max link capacity = 400Mb\s).............................................................. 33Table 7 Non City Area (Max link capacity = 200Mb\s) ..................................................... 33Table 7: Synchronisation source and distribution summary .............................................. 36Table 8: DCN network configuration per vendor................................................................. 41Table 9: NSI transmission network KPIs and reporting structure .................................... 44Table 10: Core site build guidelines ..................... ..................... ...................... ...................... ...... 51Table 11: Backhaul site build guidelines ..................... ...................... ...................... .................... 56Table 12: Access site categories ................... ...................... ...................... ...................... ............. 57Table 11: Access site consolidationNo 3PP services in place ............................. .................... 63Table 12: Outdoor cabinet consolidation existing 3PP CPE on site ............................ ............. 64
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
5/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 5 of 64
1.0 Introduction
1.1 Background
The aim of this document is to detail the design and architecture principles to
be applied across the Netshare Ireland (NSI) transmission network. NSI, as
detailed in the transition document, is tasked with collapsing the existing
transmission networks inherited from both Vodafone Ireland and H3G Ireland
onto one single network carrying all of each operators enterprise and mobile
services. As detailed in the transition document it is NSIs responsibility to
ensure that the network is future proof, scalable and cost effective with the
capability to meet the short term requirements of network consolidation and
the long term requirements of service expansion.
1.2 Scope of document
This document will detail the proposed solutions for the access and backhaul
transmission networks and the steps required to migrate from the current
separate network configuration to one consolidated network. While the
required migration procedures are detailed within this document timescales
required to complete these works are out of scope.
1.3 Document structure
The document is structure as follows:
Section 2 describes the desired end to end solution for the consolidatednetwork and the criteria used to arrive at each design decision
Section 3 covers the site design and build rules
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
6/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 6 of 64
2.0 Proposed Network architecture
As described in section 1.1, NSI is required to deploy and manage a
transmission network which is future proof, scalable and cost effective. As
services, particularly mobile, move to an all IP flat structure it is important to
ensure that the transmission network is evolved to meet this demand.
Traditionally transmission networks and the services that ran across them
were linked in the sense that the service connections followed the physical
media interconnections between the network nodes. For all IP networks
where any to any logical connections are required, it is essential that the
transmission network decouples the physical layer from the service layer.
For NSI Ireland the breakdown between the physical and service layer can be
described as:
Physical media layer
1. Tellabs 8600 & 8800 multiservice routers
2. Ethernet Microwave (Ceragon / Siae)
3. Dark Fibre (ESB / Eircom / e|net)
4. Vodafone DWDM (Huawei)
5. SDH (Alcatel Lucent/Ericsson)
6. POS / Ethernet (Tellabs)
7. Managed Ethernet services (e|net, UPC,ESBT, Eircom)
8. BT Total Transmission network (TT)
Service layer
o IP/MPLS (Tellabs / BT TT)
o L2 VPN (Tellabs / BT TT)
o E-Line (Ceragon / Siae)
o TDM access (Ceragon / Siae / Ericsson MiniLink)
By decoupling the physical media layer from the service layer it allows NSI the
flexibility to modify one layer without impacting the other. Therefore routing
changes throughout the network are independent of the physical layer once
established. In the same way changes in the physical layer such as new
nodes or bandwidth changes are independent of the service routing. This in
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
7/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 7 of 64
turn ensures that transmission network changes requiring 3rd party
involvement are restricted primarily to the physical layer which, once
established, should be minimal.
While seamless MPLS from access point through to the core network is
possible, for demarcation purposes the NSI transmission network will
terminate at the core switch (BSC / RNC / SGw / MME / Enterprise gateway).
2.1 Transmission network
Figure 1 details the proposed solution for the NSI transmission network.
680-SR12-1 680-SR12-2
HPD-SR12-1
HPD-SR12-2
RNCs 1-8 I CS U OM U
UP CP O&M
GPOP-SR12
BT TT Network
Access7210
Cgn
Cgn
Cgn
Cgn
Cgn
Cgn
Cgn
Cgn
elp?
RSTP ?
Cgn
Cgn
UP
CP
O&M
TOP
RBS
Ge
UP VID= 3170 172.17.x.x/32CP VID= 3180 172.18.x.x/32
O&MVID= 3190 172.19.x.x/32TOP VID= 3200 172.20.x.x/32
CGNO&M= 3210 172.21.x.x/32
UP
CP
O&M
TOP
RBS
GeAccessCluster
- Each VLAN =Broadcast Domain
- MAC Learning enabled throughout theclusterto enable layer2 switching
- No E-Linesin use
UP VID= 3170 172.17.x.x/32CP VID= 3180 172.18.x.x/32
O&MVID= 3190 172.19.x.x/32TOP VID= 3200 172.20.x.x/32
CGNO&M= 3210 172.21.x.x/32
dn1rnc01 172.30.213.0/24
172.30.214.0/24
172.30.215.0/24
172.30.216.0/24
172.30.217.0/24
172.30.218.0/24
dn1rnc02 10/196.0.0/20
dn1rnc03 10.196.16.0/20
dn1rnc04 10.196.32.0/20
dn1rnc05 10.196.48.0/20
dn1rnc06 10.196.64.0/20
dn1rnc07 10.196.80.0/20
dn1rnc08 10.196.96.0/20
/29netrworkallocated tobackendBTS interface.
Staticroutes requiredtoOMU, DCNandRNCnetworks??
Tellabs86xx
Tellabs nx10Gig connecting the Data Centres
DN680 VF Clonshaugh
10G LACP
10G LACP
10G LACP
10G LACP
10G LACP10G LACP
10G LACP
10G LACP
TTEthe
rnettr
unkTTEthern
etTrunk
The BT TT Network is configuredfor L2 PtP circuits to each of theCDC locations. Dual nodes atthe Data centres may be used toload balance the traffic from thedistributed BPOP locations
Netshare IP/MPLS network. L3VPNs are configured for each ofthe srevice types from each of theoperators
TOP Server
TOPVLAN D
UPVLAN A
CPVLAN B
O&MVLAN C
UP1
VRRPIRBA250 .M IRBA230 .B
W.X.Y.Z/29
TOPVLAN D
UPVLAN A
CPVLAN B
O&MVLAN C
CPVRRP
IRBB250 .M IRBB230 .B
W.X.Y.Z/29
O&MVRRP
IRBC 250 .M IRBC 230 .B
W.X.Y.Z/29
TOP
VRRPIRBD 250 .M IRBD 230 .B
W.X.Y.Z/29
VRRP VPLS i/f
OMU Network
172.30.208.0/25
DCN Network
192.168.0.0/16
10G LACP
Tellabs8860 Tellabs8860 Tellabs8860Tellabs8860
TT Ethernet trunk
Netshare LSP
VLAN Trunk
VLAN Trunk
Netshare VLAN Trunk
Legend
UP VID= 3170 172.17.x.x/26CP VID= 3180 172.18.x.x/26
O&MVID= 3190 172.19.x.x/26TOP VID= 3200 172.20.x.x/26
CGNO&M= 3210 172.21.x.x/26
Cgn
Cgn
Siae
Siae
Siae
Cgn GigE
GigE
GigE
GigE
elp
Cgn
Cgn
Cgn
Siae
Siae
Siae
Siae
Siae
CgnCgn
Siae
SiaeSiae
GigE
Netsh
areEth
ernetT
runk
Netshare GigE/POS Trunk
Netsh
areEthe
rnet
Trunk
Figure 1 Proposed NSI transmission soluti on
To explain in detail the proposed transmission solution the network will be
broken into the following areas
Data centre Northbound interfaces
Self build backhaul
Managed backhaul
Backhaul routing
Access Microwave network
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
8/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 8 of 64
Network QoS & link dimensioning
DCN
Network synchronisation
2.1 Data Centre solution
2.1.1 Physical interconnection
VFIE and H3G operate their respective networks based on a consolidated
core.
All core switching (BSCs, RNCs, EPCs, Master synchronisation, DCN,
security) for both H3G and VFIE are located in Dublin across 4 data centres.
They are;
1. CDC1 DN680 Vodafone, Clonshaugh (VFIE)
2. CDC2 DN706 BT, Citywest (VFIE)
3. CDC3 DN422 Data Electronics, Clondalkin (VFIE)
4. CDC4 DNxxx Citadel, Citywest (H3G)
Figure 2 below details the possible northbound connections @ each data
centre
Figure 2 Example data centre northbound physical in terconnect
NSI will deploy 2 x Tellabs 8800 multiservice routers (MSRs) at each of thedata centres. 2 routers are required to ensure routing resilience for the
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
9/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 9 of 64
customer traffic. The 8800 hardware will interface directly at 10Gb\s, 1Gb\s &
STM-1 with the core switches, DCN and synchronisation networks for both
operators.
Each of the Data centres will be interconnected using n x 10Gb\s rings. RSVP
LSPs are not supported on the current release of 8800 interfaces in a Link
Aggregation Group (LAG) so multiple 10Gb\s rings can be used to transport
traffic from both operators. In the first deployment 1 x 10Gb\s ring will be
deployed which can be upgraded as required. Consideration was given to a
meshed MPLS core, however the Nx10Gb\s ring was deemed to be
technically sufficient and more cost effective. This design may be revisited in
the future based on capacity, resilience and expansion requirements.
Interfacing to the out of band DCN (mobile and transmission networks) and
synchronisation networks will be realised through 1Gb\s interfaces.
All interfaces to legacy TDM and ATM systems are achieved through the
deployment of STM-1c and STM-1 ATM interfaces.
Physical and layer 3 monitoring of the physical interfaces is active on all trunk
interfaces so in the event of a link failure all traffic is routed to the diverse path
and the required status messaging and resilience advertisements are
propagated throughout the network. These will be explained in detail in each
of the sections dealing with service provisioning.
2.2 Self build backhaul network
Self build refers to network hardware and transmission links that are within the
full control of NSI in terms of physical provisioning. The Self built Backhaul
network interconnects the aggregation sites and the core data centre
locations via a mix of Ethernet, Packed over SDH (POS) and SDH point to
point trunks. The service layer will be IP/MPLS based on the Tellabs 8600
and 8800 MSR hardware. Figures 3 and 4 are examples of the proposed
network structure,
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
10/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 10 of 64
Dublin Dark Fibre v1.0
Core Dublin ring STM16 (future 10G/nx10G/40G); ISIS L2-only or L1-2 if between routers in same location
ISIS 49.0031
DN522200
172.25.2.3
DN294200
172.25.0.8
DNBDE200
172.25.0.107
DNFTZ200
172.25.0.9
DN923200
172.25.4.2
DN017200
172.25.4.3
DNNGE201
172.25.0.109
DNBLB200
172.25.0.101
DNFOX200
172.25.0.100
DNCRL200
172.25.0.103
DNWAL200
172.25.0.102
DN875200
172.25.5.1
DNTLH200
172.25.1.4
DN394200
172.25.0.104
DNCLD200
172.25.1.2
DNLCN200
172.25.0.105
DNPAL200
172.25.1.1
DN940200
172.25.5.2
DNCME200
172.25.1.6
DNCAB200
172.25.2.6
DN433200
172.25.6.1
DNCP1200
172.25.1.5
DN113200
172.25.2.8 DNSAN200
172.25.0.106
DN915200
172.25.4.1
DNDCT200
172.25.x.y
DN822200
172.25.5.3
DNSE1200
172.25.2.4
DN880200
172.25.3.2
DNTWR200
172.25.2.5
DNHB1200
172.25.0.7
DNAGI200
172.25.64.1
ISIS 49.0032
ISIS 49.0033
DNBW1200
172.25.128.1
PoC2 connections GE (future 10G); ISIS L1-2 intra-area links or L2-only inter-area links
PoC3 connections GE (future subrate_10G/line_rate_10G); ISIS L1-only
PoC3 connections GE; ISIS L1-only
DN680200
172.25.0.1
DN680201
172.25.0.2
DN680202
172.25.0.17
DN422201
172.25.0.6
DN422200
172.25.0.5
DN706200
172.25.0.3
DN706201
172.25.0.4
DNNGE200
172.25.3.3
DNPRP201
172.25.0.110
DNPRP200
172.25.3.1
DN419200
172.25.2.2
DNBLP200
172.25.2.1
DNBLP201
172.25.x.y
ge12/0/7
ge6/0/7
ge9/0/7
ge8/0/7
ge8/0/7
ge7/0/7ge8/0/7
ge2/0/7
ge13/0/7ge5/0/7
ge10/0/7
ge6/0/7
ge9/0/7
so10/0/0
so5/0/0
so6/1/0so9/1/0so8/1/0
so7/1/0
so6/1/0
ge8/0/7
ge7/0/7
ge6/0/7
ge9/0/7
ge8/0/7
ge7/0/7
ge5/0/7
ge10/0/7
ge3/0/7so7/1/0so6/1/0so9/1/0 so8/1/0 so7/1/0s o8 /1 /0 s o8/ 1/ 0s o9 /1 /0so6/1/0
so6/1/0
so7/1/0
so5/0/0
so9/0/0
so9/0/0so6/0/0
ge9/0/6
ge3/0/7
ge6/0/7
ge9/0/7
ge6/0/7
ge9/0/7 ge6/0/7ge9/0/7
ge10/0/7
ge5/0/7
ge9/0/7ge6/0/7 ge6/0/7 ge9/0/7 ge7/0/7 ge8/0/7
ge3/0/7
g e 12 / 0/ 7 g e 6/ 0 /7
ge9/0/7
ge9/0/0
ge9/0/7
g
e6/0/0
ge6/0/7
ge7/0/7
ge8/0/7
ge6/0/7
ge9/0/7
ge7/0/7
ge8/0/7
ge8/0/0
ge7/0/0
ge6/0/7
ge9/0/7
ge12/0/7
ge12/0/6
ge11/0/7
ge3/0/7
ge8/0/7ge7/0/7
ge7/0/7
ge8/0/7
ge10/0/7
ge5/0/7
ge9/0/7
ge6/0/7
ge9/0/7 ge6/0/7
ge5/0/7
ge10/0/7ge5/0/7ge10/0/7ge7/0/7
ge8/0/7
ge7/0/7ge8/0/7
ge3/0/7
ge12/0/7
ge7/0/7
ge8/0/0
ge7/0/0
ge6/0/7
ge9/0/7
ge8/0/0
g e7 /0 /0 g e6 /0 /7
ge9/0/7ge8/0/7ge7/0/7
ge8/0/7
ge9/0/7
ge7/0/6
ge8/0/6
ge9/0/7
ge6/0/6
34 10.82.0.32/30 33
18
10.
82.0.1
6/30
17
26
10.
82.
0.
24/30
25
17
10.
82.0.
16/30
18
30 10.82.0.28/30 29
37
10.8
2.
0.
36/30
38
21 10.82.0.20/3022
110.82.0.0/30 2
510.82.0.4/306
910.82.0.8/30 10
13 10.82.0.12/30 14 98 10.82.0.96/3097
1 10.82.10.0/30 2
6
10.
82.1
0.
4/30
5
10
10.
82.
10.8
/30
9
14
10.8
2.
10.1
2/30
13
18 10.82.10.16/30 17
2210.82.10.20/30 21
25
10.
82.1
0.
24/30
26
29
10.
82.1
0.
28/30
30
33
10.8
2.
10.
32/30
34
37
10.
82.
10.3
6/30
38
41
10.8
2.
10.
40/30
42
45 10.82.10.44/30 46
49 10.82.10.48/30 50
53 10.82.10.52/30 54
22110.82.10.220/30222
22610.82.10.224/30225
58
10.8
2.
10.
56/30
57
62 10.82.10.60/30 61
66
10.
82.1
0.
64/30
65
234
10.8
2.1
0.2
32/30
233
229
10.8
2.1
0.2
28/30
230
70 10.82.10.68/30 69 7410.82.10.72/30 73
78
10.
82.1
0.
76/30
77
81
10.
82.1
0.
80/30
828610.82.10.84/30 85
89
10.
82.
10.8
8/30
90
93
10.8
2.
10.9
2/30
94
9710.82.10.96/30 98
102
10.8
2.
10.
100/30
101
105 10.82.10.104/30 106
109
10.
82.1
0
.108/30
110
113 10.82.10.112/30 114117 10.82.10.116/30 118
125 10.82.10.124/30 126
121
10.8
2.
10.
120/30
122
129 10.82.10.128/30 130
134
10.
82.
10.1
32/30
133
13710.82.10.136/30 138
142
10.
82.1
0.
140/30
141
237
10.8
2.1
0.
236/30
238
242
10.
82.1
0.2
40/30
241
245 10.82.10.244/30246
DN419201
172.25.0.108
25010.82.10.248/30249
146
10.
82.1
0.
144/30
145
150
10.
82.1
0.
148/30
149
15410.82.10.152/30 153
Sync Priority 1
Sync Priority 2Sync Priority 3
U1U1
4
U1
U14
From
_AD
M
From_
ADM
From_ADMFrom_ADMFrom_ADM
From
_ADM
L1BL1B L1B L1B L1B L1B
L1BL1A L1A
L1A
L1AL1AL1A
L1A
L 1A L 1A
L1B
L2B
L2B
L2B
L2B
L2B
L2B
L2B
L2B
L2B
L2B
L2B
L2B
L2B
L2B
L2B
L2B
L2B
L2BL2B
L2B
L2B L2B
L2B
L2B
L2B
L2B
L2B
L2B
L2B
L2BL2B
L2B
L2B
L2B
L2B
L2B
L2B
L2B
L2BL2B
L2B
L2B
L2B
L2B
L2B
ge7/0/7
ge7/0/7
L3B
L3B
L2B
L2B
L2B
L2B
L2B L2B
Figure 3 - Dublin Dark f ibre IP/MPLS network
In the network Dark fibre from Eircom, ESB and e|net will be used as the
physical media interconnect. Interconnections based on aggregation
requirements will be at speeds of 1Gb\s, 2.5Gb\s (legacy) or 10Gb\s. A
hierarchical ISIS structure of rings will be used to simplify the MPLS design.
The Level 2 areas will be connected directly to the core data centre sites with
level 1 access rings used to interconnect traffic from the access areas. The L2
access areas will have physically diverse fibre connections to 2 of the data
centres. Physically diverse LSPs are routed from the L2 aggregation routers
to each of the data centres facilitating diverse connectivity to each of the core
switching elements. This provides protection against a single trunk or node
failure.
The access rings will have diverse fibre connectivity to a L1/2 router which will
perform the ABR function.
Within each access ring diverse LSPs will be configured to the ABR or ABRs
providing access route resilience against a single fibre break and/or node
failure.
RSVP LSPs with no bandwidth reservations will be used to route the LSPs
across the backhaul network. All LSPs will use a common Tunnel Affinity
Template. This provides the flexibility to re-parent traffic to alternative trunks
without a traffic intervention should that be required. It is proposed to use a
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
11/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 11 of 64
combination of strict and loose hop routing across the network. The working
path should always be associated with the strict hop with the protection
assigned to either a strict or loose hop. For those LSPs routed over the
Microwave POS trunks, strict hops will be used to ensure efficient bandwidth
management. For those routed across Dark fibre or managed Ethernet loose
hops will be used. In a mesh network where there are multiple physical
failures and multiple paths possible this approach offers a greater level of
resilience.
LH038200172.25.0.16
DN706201172.25.0.4
DN680200172.25.0.1
DNBW1200172.25.128.1
KECAP200172.25.128.2 MHFKS200
172.25.128.5
MHWD1200172.25.128.3
WHLIN200172.25.128.6
MH009200172.25.128.7
LH001200172.25.128.8
LH011200172.25.128.9
CNSGA200172.25.128.11
CNMCR200172.25.128.12
LHDDK200172.25.128.14
10/1/4
10/1/7
10/1/6
10/1/5
7/0/0
7/0/3
7/0/2
7/0/1
8/0/0
8/0/38/0/28/0/1
7/0/0
7/0/37/0/27/0/1
8/0/0
8/0/3
8/0/2
8/0/1
9/0/0
9/0/2
9/0/2
9/0/1
7/0/0
7/0/3
7/0/2
7/0/18/0/0
8/0/3
8/0/2
8/0/1
9/0/0
9/0/3
9/0/2
9/0/1
4/0/4
4/0/7
4/0/6
4/0/5
7/0/0
7/0/37/
0/2
7/0/1
8/0/0
8/0/3
8/0/2
8/0/1
7/0/2
7/0/1
7/0/0
7/0/3
9/0/0
9/0/3
9/0/2
9/0/1
8 / 0 / 0
8 / 0 / 3
8 / 0
/ 2
8 / 0 / 1
8/0/0
8/0/3
8/0/2
8/0/1
7/0/0
7/0/3
7/0/2
7/0/1
8/0/0
8/0/3
8/0/2
8/0/1
7/0/0
7/0/3
7/0/2
7/0/1
9/0/0
9/0/3
9/0/2
9/0/1
7/0/0
7/0/3
7/0/2
7/0/1
8/0/0
8/0/3
8/0/2
8/0/1
7/0/0
7/0/3
7/0/2
7/0/1
8/0/0
8/0/3
8/0/2
8/0/1
7/0/0
7/0/3
7/0/2
7/0/1
7/0/0
7/0/3
7/0/2
7/0/1
8/0/0
8/0/3
8/0/2
8/0/1
8/0/0
8/0/3
8/0/2
8/0/1
7/0/0
7/0/3
7/0/2
7/0/1
8 / 0 / 0
8 / 0 / 3
8 / 0 / 2
8 / 0 / 1
7/0/4
7/0/4
8/0/4
1
10.
82.
128.
0/30
2
1710.82.128.16/30
18
5
10.
82.
128.
4/30
6
9
10.
82.
128.
8/30
10
13
10.
82.
128.
12/30
14
2510.82.128.24/30
26
2110.82.128.20/30
22
2910.82.128.28/30
30
33 10.82.128.32/30 34
45 10.82.128.44/30 46
41 10.82.128.40/30 42
37 10.82.128.36/30 38
77 10.82.128.76/30 78
73 10.82.128.72/30 74
69 10.82.128.68/30 70
65 10.82.128.64/30 66
81
10.8
2.12
8.80
/30
82
93
10.82
.128.92
/30
94
89
10.82
.128
.88/30
90
85
10.8
2.128.84
/30
86
97
10.82
.128
.96/3
098
101
10.82.128.100/30
102
113
10.82.128.112/30
114
109
10.82.128.108/30
110
105
10.82.128.104/30
106
21 10.82.129.20/30 22
125 10.82.128.124/30 126
121 10.82.128.120/30 122
117 10.82.128.116/30 118
129 10.82.128.128/30 130
141 10.82.128.140/30 142
137 10.82.128.136/30 138
133 10.82.128.132/30 134
145 10.82.128.144/30 146
157 10.82.128.156/30 158
153 10.82.128.152/30 154
149 10.82.128.148/30 150
161
10.
82.
128.
160/30
162
173
10.
82.
128.
172/30
174
169
10.
82.
128.
168/30
170
165
10.
82.
128.
164/30
166
177
10.
82.
128.
176/30
178
181
10.82.128.180/30
182
193
10.82.128.192/30
194
189
10.82.128.188/30
190
185
10.82.128.184/30
186
197 10.82.128.196/30 198
209 10.82.128.208/30 210
205 10.82.128.204/30 206
201 10.82.128.200/30 202
213 10.82.128.212/30 214
225 10.82.128.224/30 226
221 10.82.128.220/30 222
217 10.82.128.216/30 218
241 10.82.128.240/30 242
237 10.82.128.236/30 238
233 10.82.128.232/30 234
229 10.82.128.228/30 230
2 4 5
1 0
. 8 2
. 1 2 8
. 2 4 4 / 3
0
2 4 6
1
1 0
. 8 2
. 1 2 9
. 1 / 3
0
2
2 5 3
1 0
. 8 2
. 1 2 8
. 2 5 2 / 3
0
2 5 4
2 4 9
1 0
. 8 2
. 1 2 8
. 2 4 8 / 3
0
2 5 0
8/0/0
8/0/3
8/0/2
8/0/1
MHSKE200172.25.128.4
7/0/0
7/0/3
7/0/2
7/0/1
61 10.82.128.60/30 62
57 10.82.128.56/30 5853 10.82.128.52/30 5
449 10.82.128.48/30 5
0
Figure 4 - National North East area I P/MPLS microwave network
Figure 4 details a sample of the self built backhaul network routed over N+0
SDH microwave links and rings. In this situation LSPs are routed over
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
12/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 12 of 64
multiple hops to the data centres and all routers will be added to the Level 2
area. In order to ensure that traffic is correctly balanced across the SDH
trunks RSVP LSPs will be routed statically giving NSI a greater level of
control over the bandwidth utilisation. LSPs from each collector will be
associated with a particular STM-1 and routed to the destination accordingly.
Traffic aggregating at each collector is then associated with a particular LSP.
NOTE: The transition document states that the National SDH Microwave
network should be replaced by NSI with the BT TT network (See section
2.1.2) or a National DF network. However, as this will take time and
consolidated sites are required nationally in the short term, the network
described in Figure 4 will be utilised over the short to medium term.
2.3.1 Self build fibre diversity
The table below details the physical diversity requirements for fibre based on
traffic aggregation in the transmission network. Note that in some cases
where the capital cost to provide media diversity over fibre is prohibitive
Microwave Ethernet will be considered as a medium term alternative. While
the microwave link will for the most part be of a lower capacity than the
primary fibre route the degradation of service during the fibre outage may beacceptable for short periods to maximise the fibre penetration
Aggregation level Diversity Comments
< 5 Single fibre pair No diversity
5 x 9 Flat ring Two fibre pairs sharing
the same duct
> 9 Fibre duct diversity 5m fibre separation to
the aggregation router
Table 1: Self build fibre diversity
Note that the above table details the desired physical separation. In some
cases the physical separation may not be physically possible and a decision
on the aggregation level will be made based on other factors such as location,
security, landlord, antenna support structure and cost.
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
13/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 13 of 64
2.3 Managed backhaul
Managed backhaul refers to point to point or network connections facilitated
by an OLO over which NSI will transport traffic. In this case the OLO will
provision the physical transmission interconnections.
Presently VFIE use Eircom and e|net as a managed service vendor. In this
case VFIE have individual leased lines from each of the vendors providing
point to point fixed bandwidth connections.
H3G to date have used BT as their backhaul transmission vendor where all
traffic from the access network is routed across the National BT Total
Transmission (TT) network.
2.3.1 TT Network contractThe BT TT contract allows H3G to utilise up to 70Gb\s of bandwidth across a
possible 200 collector or aggregation locations. Presently BT has configured
multiple L3VPNs across the TT to route traffic between the collector locations
and the data centre site at Citadel (Citywest).
BT deployed 2 x SR12 (ALU) routers at Citadel to terminate all of the traffic
from the possible 200 x locations.
H3G can interconnect from their access network at a BT GPOP onto a
collocated SR12 or APOP. At an APOP BT deploy an Alcatel-Lucent (ALU)
7210 node and extend the TT to this point. The physical resilience from the
GPOP to the APOP depends on the traffic to be aggregated at the site. See
Table 2.
Collector
Type
Sites
aggregated
Physical resilience Comments
Small 5 None
Medium 5 < x 9 Flat ring
Large 10 Diverse fibre duct
Table 2: TT Access fibre diversity
Figure 5a details the configuration of the BT TT solution.
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
14/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 14 of 64
Figure 5aBT Total Transmission network
Because BT route traffic to and from the collector points over L3VPNs theymust be involved in the provisioning process for all RBS across the network.
As described in section 2.0 it is proposed to separate the physical
interconnection of sites from the service provisioning for NSI. To achieve this
across the TT NSI must use the TT to replicate physical point to point
connections across the backhaul network.
It is proposed to change the BT managed service from a Layer 3 network to a
layer 2 network and replicate the approach taken in the self built network. Theend result being that the provision of services across the NSI backhaul
network is consistent regardless of the underlying physical infrastructure (Self
built or managed).
In order to replicate the self built architecture and utilise the BT TT contract it
will be necessary to extend the TT network to a second data centre. It is
proposed to extend the BT TT to the VFIE date centre in Clonshaugh.
At Citadel and Clonshaugh the TT will interconnect with the 8800 network on
Nx10Gb\s connections. While it is not necessary to deploy 2 x SR-12 TT
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
15/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 15 of 64
routers at the data centres due to the path resilience employed, it will be
useful in terms of load balancing and future bandwidth requirements. As with
the self build design, resilience will be achieved through the physical path
diversity to diverse data centre locations from each of the BT GPoPs.
Figure 5b illustrates the physical and logical connectivity across the BT TT.
BT
Total Transmission
Core
L1/2
BT - Alcatel7210- Collector
1Gbit/s
1Gbit/s
BT
IP GPoP
Ballymount
BT
IP GPoP
HPD 2
10Gb
BT
IP GPoP
HPD 1
10Gb
10Gb\ s NSI MPLS 10Gb\ s NSI MPLS10Gb\ s NSI MPLS
Symmetricom
TP500
ge
P1_1588v2
P1_SyncE
E-Lines on BT
TT
Citadel
100Clonshaugh
ADVA
XG210
NSI
MPLS ABR
(1)
L1/2
SymmetricomTP500
ge
P1_1588v2
P1_SyncE
NSI
MPLS ABR
(2)
ADVA
XG210
NSI MPLS
Collector
1G/10G 1G/10G 1G/10G 1G/10G
1G/10G
1Gb\s 1Gb\s
Primary &
secondary
LSPs
E-Lines from BT
Collector to
GPOP
Figure 5b
NSI logical and physical transmission across the BT network
VLAN trunks over E-Lines are configured from the collector to the GPOP over
which LSPs are configured to the ABRs using LDP. LDP will facilitate
automatic label exchange within the MPLS network and remove the
requirement for manual configuration in the access area.
In the BT TT network, VLAN trunks over E-Lines are configured for each ABR
to one of the parent data centres. RSVP-TE LSPs can be configured across
these trunks to any of the data centre facilities in a resilient manner.
Dual ABRs are used to ensure hardware resilience for the access areas
where up to 20 collector nodes could be connected to a BT GPOP in this
manner.
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
16/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 16 of 64
2.3.3 Backhaul network selection
In some cases NSI will have the option to use either self build dark fibre or
managed services to backhaul services from a particular aggregation point. In
this case a number of factors must be considered when selecting the network
type. They are;
Factor Self Build Managed Comment
Long term
bandwidth
requirements
High Low /
medium
For large bandwidth sites
dark fibre may offer the
more attractive cost per bit
Operational Cost
impact
High/Medium Low To reduce the impact on
the operational expenditure
dark Fibre CapEx deals
may be more attractive
Surrounding
network
Dark fibre Managed The transmission network
selection should take
account of the surrounding
backhaul type. This is to
ensure that the
interconnecting clusters are
optimally routed through
the hierarchical structure.
2.4 Backhaul routing
Backhaul routing can be split into legacy (TDM/ATM) services, enterprise
services and IP services.
2.4.1 Legacy mobile services
Legacy mobile services relate to 2G BTS and 3G RBS nodes with TDM and
ATM interfaces. For these services NSI will configure pseudowires (PWEs)
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
17/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 17 of 64
across the MPLS network. ATM services will be carried in ATM PWEs with
N:1 encapsulation used for the signalling VCs to reduce the number required.
Userplane VCs can be mapped into single PWE. TDM services will be
transported using SAToP PWEs. At the core locations MSP1+1 protected
STM-1 interfaces will be deployed between the 8800 MSRs and the core
switches (BSC / RNC).
Note: Multichassis MSP feature is not available on the Tellabs 8800 MSRs.
Therefore MSP1+1 protecting ports will be on separate cards.
At the access locations MSP protection for ingress TDM traffic will be
configured in the same way on the 8600 nodes.
PWEs for legacy services will be routed between the core and collector
locations over physically diverse LSPs.
2.4.2 Enterprise services
Similar to legacy services, enterprise services will be routed between the core
and collector locations over diverse or non diverse LSPs based on the
customers SLA. For the most part enterprise services are provided as
Ethernet services. In this case Ethernet PWEs will be configured to carry the
services. A Class of Service (CoS) will be applied to the Ethernet PWE basedon the customers SLA.
At the core locations the service will be handed to the customer network over
an Ethernet connection with VLAN separation for the individual customers. In
the event that multiple customers are sharing the same physical interfaces
SVLAN separation per customer can be implemented. This will be finalised
based on a statement of requirements from the parent operator.
TDM services for enterprise customers will be treated the same as legacy
TDM services described in 2.4.1 with STM-1 interfaces used to interface the
core switches
2.4.3 IP services
2.4.3.1 L3VPN structure
For IP services L3VPNs will be configured across the MPLS network.All
routing information will be propagated throughout each L3VPN using BGP.
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
18/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 18 of 64
The IP/MPLS network will be configured in a hierarchical fashion with route
reflectors used to advertise routing within each area. Route Reflectors (RRs)
will be implemented in the core area with all level 2 routers peering to those
RRs. The ABRs between the level 1 and 2 areas will act as the route
reflectors for the connected level 1 areas. This will reduce the size and
complexity of the routing tables across the network.
For each service a L3VPN will be configured. Because H3G and VFIE use
different vendors and have different requirements in the core the number of
L3VPNs required differ slightly. Table 3 details the L3VPNs to be configured
across the NSI network.
Parent L3VPN Description Comment
VFIE 2G UP User Plane Separate L3VPNs are configured for
each BSC
VFIE SIU O&M Baseband
aggregation switch
VFIE RNC UP 3G User Plane Separate L3 VPN are configured for
each RNC
VFIE SRAN O&M SRAN O&M
VFIE Synchronisation 1588v2 network
VFIE Siae O&M Ethernet
microwave O&M
VFIE MiniLink O&M O&M for the
MiniLink PDH
network (SAU-IP)
H3G 3G UP User plane A single L3VPN for all RNCs
H3G 3G CP Control plane A single L3VPN for all RNCs
H3G 3G O&M (RNC) Operation and
maintenance
A single L3VPN for all RNCs
H3G 3G O&M RBS Operation and
maintenance
A single L3VPN for all RBS
H3G TOP 1588v2 network Synchronisation
H3G Ceragon O&M Ethernet
Microwave O&M
VFIE LTE Tbc Tbc
H3G LTE Tbc Tbc
Table 3 List of L3VPNs required
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
19/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 19 of 64
As services are added to the network they will be added as endpoints to the
respective L3VPN for that service and parent core node. This is achieved by
adding the endpoint interface and subnet to the VPN. Any adjacent network
routing required to connect to a network will be redistributed into the VPN
also.
VFIE use /30 subnets to address the mobile services across the network. This
results in a large number of endpoints within each L3VPN. For that reason the
networks will be split based on the parent core switch. This results in a L3VPN
for each of the services routed to each of the RNCs/BSCs. For the H3G
network, /26 networks are typically used at each of the endpoints. This
summarisation reduces significantly the number of endpoints required within
each VPN and consequently the number of VPNs.
Sections 3 and 4 detail the impacts the proposed design have on each of the
operators existing solutions and the steps, if any, required to migrate to the
proposed solution.
2.4.3.2 IP service Resilience
Transport resilience
Within the backhaul network IP services will be carried resiliently between the
core and collector locations over diversely routed LSPs. It is proposed to use
a combination of strict and loose hop routing across the network. The working
path should always be associated with the strict hop with the protection
assigned to the loose hop. By configuring the protection on a loose hop it will
allow the IGP to route the LSP between the source and destination. In the
event of a failure all traffic will be switched to the protecting LSP which has
been routed between the source and destination via the IGP. In a mesh
network where there are multiple physical failures and multiple paths possible
this approach offers a greater level of resilience.
Note, as described in section 2.2, in the case where both the main and
protecting paths are routed over Microwave STM-1 trunks, strict hop routing
will be employed for both paths to ensure optimum utilisation of the available
capacity.
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
20/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 20 of 64
Router Resilience
Within the level 2 area of the network dual routers are deployed to ensure
resilience at locations aggregating large volumes of traffic. In this case
resiliently LSPs are routed from the collector nodes to both routers. In the
event of a router failure traffic will route over the operating router until such
time as the second router is operational after which the routing will return to
the initial configuration.
Core switch resilience - VRRPFor all connections to the mobile core, Virtual Router Redundancy Protocol
(VRRP) should be used. While the VRRP implementation will differ slightly
based on the mobile core vendor and function, the objective is to ensure that
the transmission network to the core has full interface and router redundancy.
10Gb\s (with LAG if required) cross links at each data centre location between
the 8800 nodes will be implemented to support the router redundancy.
For the 8800 nodes during restart it is possible that the router will advertise
the interface addresses to the core switch (BSC/RNC/SGw/MME) before the
router forwarding function is re-established. This may result in the temporary
Black Holing of traffic. To avoid this scenario a separate connection is
required between the routers with a default route added to each for all traffic.
This will avoid the above scenario. It is proposed that a 10Gb\s link should be
used for this also.
2.5 Access Microwave network
The target access microwave network with be based on an Ethernet
microwave solution utilising ACM to maximise the available bandwidth. In the
existing networks H3G use Ceragon IPx Microwave products while VFIE use
the Siae Alc+2 and Alc+2e products. While it is envisaged that NSI will tender
for one supplier it is not planned to replace one of the existing networks. The
access network solution must be designed so as to ensure both vendors
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
21/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 21 of 64
products and the services transported across them inter operate without
issue.
Figure 7 details a possible configuration of the access network topology
utilising both vendors products.
Cgn
Cgn
Siae
Siae
Siae
CgnGigE
GigE
GigE
GigE
elp
Cgn
Cgn
Cgn
Siae
Siae
Siae
Siae
Siae
CgnCgn
Siae
Siae Siae
GigE
Cgn
Cgn
Aggregation Node 86xx
Figure 7Access M icrowave topology
2.5.1 Baseband switching
For the access network all traffic will be routed at layer 2 utilising VLAN
switching at each point. VLANs will be statically configured at each site on
each of the indoor units. For VFIE, unique VLANs are used to switch traffic
from each of the RBS nodes. For H3G, common VLANs are used for each of
the service types switched across the network. They are;
UP VID = 3170
CP VID = 3180
O&M VID = 3190
TOP VID = 3200
Ceragon O&M = 3210
Note: Future developments may result in the deployment of all outdoor MW
Radio products in the traditional MW Bands and in the E-Band. In this case at
feeder locations a cell site router may be deployed to perform the baseband
switching function using IP/MPLS routing functions. Should this solution be
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
22/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 22 of 64
employed in the future, an additional design scenario will be described and
added to this document.
2.5.2 Microwave DCN
All Microwave DCN will be carried in band (this is already the case for the
Ceragon network elements). As sites are consolidated and migrated to the
consolidated network, it will be necessary to migrate the Siae DCN solution to
an in band solution. It is proposed to assign VLAN ID 3000 to the Siae
network for DCN.
2.5.3 Backhaul Interconnections
The access network will interface with the backhaul network over multiple GE
interfaces. The interfaces can be protected or not depending on the capacity
requirements. While LAG is possible on the GE interfaces the preference will
be to use ELP on the access router with interconnected IDU interfaces in an
active / active mode.
In a situation where greater than one 1Gb\s is required over the Radio link,
LAG can be used. The limitation on the access interfaces is that the interfaces
in a LAG on the Tellabs 8600 must be on the same interface module. This is aplanned feature for release FP4.1 and is planned to be deployed in the NSI
network forQ2 2014.
VSI interfaces will be used to associate common network VLANs arriving on
separate physical interfaces to a common virtual interface. This ensures that
the approach used to assign a single subnet per traffic type per cluster can be
continued where required. A separate VSI interface will be configured for each
service type and added as the endpoint to the required IPVPN. Any static
routes required to connect to and from the DCN network will use the VSI
interface address. Figure 8 details the operation of the VSI interface.
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
23/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 23 of 64
GE
GE
GE
VSIVSI
VSI
GE
GE
GE
Cgn
Cgn
Siae
VID3170
VID3210VID3000
VID3000
VID3210VID3170
VID3000VID3210
VID3170
VID3000
VID3210VID3170
VID3000
VID3210VID3170
VID3000
VID3210VID3170
VID3000 Siae DCN
VID3210 Ceragon DCNVID3170 H3G UP
VID3000
Siae DCN
VID3210 Ceragon DCNVID3170 H3G UP
VID3000 Siae DCN
VID3210 Ceragon DCNVID3170 H3G UP
Tellabs 86xx
Figure 8Example VSI grouping conf iguration
2.6 Network topology & traffic engineering
The NSI transition document details the targets for network topology, traffic
engineering and bandwidth allocation on a per site basis for each of the
mobile networks. In summary they are;
No more than 1 Microwave hop to fibre (Facilitated by providing fibre
solutions to 190 towns)
No contention for shared transmission resources (NSI are required to
monitor utilisation and ensure upgrade prior to congestion on the
transmission network)
Traffic engineering (CoS, DSCP, PHB) will be assigned equally to each
service type from each operator. At a minimum the following will be
applied;
o Voice (GBR)
o Video/interactive (VBR-RT)
o Enterprise (VBR-NRT)
o Data (BE)
Bandwidth allocation per site
o Dublin & other cities (400Mb\s\site)
o Towns (5 10K) (300Mb\s\site)
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
24/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 24 of 64
o Rural (200Mb\s\site)
This chapter will explain in detail the required Access, Backhaul and Core
transmission network dimensioning guidelines and traffic engineering rules to
achieve the targets set out in the transition document
2.6.1 Access Microwave topology & dimensioning
The national access microwave network will be broken into clusters of
microwave links connected, over one or multiple hops, to a fibre access point.
The fibre access point can be part of the self built or managed backhaul
networks but must have the following characteristics;
Long term lease or wholly owned by NSI or one of the parent operators
24 x 7 access for field maintenance
Excellent Line of Site properties
Facility to house a significant number of microwave antennas
Space to house all the required transmission nodes and DC rectifier
systems
No Health and safety restrictions
Before creating a cluster plan, each site in the MW network must be classified
under the following criteria;
Equipment support capabilities
Line of sight capabilities proximity to existing fibre solution
Existing frequency designations
Site development opportunities
Landlord agreements (Number and type of equipment/services
permitted under the existing agreements)
Term of agreement
Creating a database as above will allow the MW network planning team to
create cluster solutions where a number of sites are associated with a
designated head of cluster. As per the transition document the target topology
is one hop to a fire access point. However this will not always be possible due
to one or a combination of the following factors;
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
25/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 25 of 64
Line of Site
Channel restrictions
Proximity of fibre solutions
Once the topology of the cluster is defined it is necessary to define thecapacity of each link within the cluster. For tail links this is straight forward, the
link must meet the capacity requirements of the transition document;
Dublin & other cities (400Mb\s\site)
Towns (5 10K) (300Mb\s\site)
Rural (200Mb\s\site)
For feeder links, statistical gain must be factored while still meeting the
capacity requirements for each of the individual sites. Table 4 gives examplesof existing MW Radio configurations and the average air interface speeds
available.
Channel
Bandwidth
Configuration Max Air interface speed @
256QAM
14MHz Single channel 85Mb\s
28MHz Single channel 170Mb\s
28Mhz 2 channel LAG 340Mb\s
28MHz 3 channel LAG 500Mb\s
28MHz 4 channel LAG 680Mb\s
56Mhz Single Channel 340Mb\s
56MHz 2 channel LAG 680Mb\s
56MHz 3 channel LAG 1.02Gb\s
56MHz 4 channel LAG 1.34Gb\s
E-Band 1GHz 1Gb\s
Table 4 Radio configuration V air interface bandwidth
Table 5 provides a guide for feeder link configurations based on the number
of physical sites aggregated across that link.
Physical sites
aggregatedCity Urban Rural Comments
2P1: E-band
P2: 2 x56MHzP1: 1 x56MHz P1: 1 x56MHz 3:1 Stat gain
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
26/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 26 of 64
3P1: E-band
P2: 2 x56MHzP1: 1 x56MHz P1: 1 x56MHz 3:1 Stat gain
4P1: E-band
P2: 2 x56MHzP1: 2 x56MHz P1: 1 x56MHz 3:1 Stat gain
5 P1: E-band
P2: 2 x56MHzP1: 2 x56MHz P1: 1 x56MHz 3:1 Stat gain
6P1: E-band
P2: 3 x56MHzP1: 2 x56MHz P1: 2 x56MHz 3:1 Stat gain
7P1: E-band
P2: 3 x56MHz
P1: E-band
P2: 3 x56MHzP1: 2 x56MHz 3:1 Stat gain
8P1: E-band
P2: 4 x56MHz
P1: E-band
P2: 3 x56MHzP1: 2 x56MHz 3:1 Stat gain
Table 5: Feeder link reference
Note that no more than 8 physical sites should be aggregated on any one
feeder link.
For MW links utilising adaptive code modulation (ACM) it is important that at
the reference modulation (i.e. the modulation scheme for which ComReg have
allocated the Max EIRP) is dimensioned so as to meet the sum of the CIRs
from each operator across that link.The total CIR per link is based on the product of the RAN technologies
deployed and the CIR per RAN technology.
Service RAN technology CIR (Mb\s)
Voice 2G 1
Voice 3G 1
Voice LTE 1
Data GPRS 1.5Data R99 2
Data HSxPA 15
Data LTE 20
Table 6: CIR per technology reference
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
27/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 27 of 64
Should restrictions apply in terms of hardware, licensing, topology with the
effect that links cannot be dimensioned as per table 4 then the following
formula should be used to determine the minimum link bandwidth.
Min Feeder l ink c apacity = MAX (VFIE CIR + H3G CIR, Max Tai l l ink capacity)
CIR = Total CIR across all links aggregated from each operator
Max Tail link capacity = Max tail link capacity of all sites aggregated
across the feeder link
The formula is designed to facilitate the required capacity for each site based
on location while at the same time ensuring, where multiple sites are
aggregated, that the minimum CIR is available to each site.
2.6.2 Access MW Resilience rules
The resilience rules for the access MW network are based on the number of
cell sites and enterprise services aggregated across the link. 1+1 HSB will be
used to protect the physical path.
Collector site Sites
aggregated
Physical resilience Comments
Small 5 None
Medium /
Large
> 5 1+1 HSB
Note that while LAG can be considered as a protection mechanism, allowing
the link to operate at a lower bandwidth in the event of a Radio failure, NSI will
protect the Radios in a LAG group using 1+1HSB to ensure the highest
hardware availability for a physical link. NSI will consider LAG for capacity
only and 1+1 HSB for protection.
The target microwave topology, as described in the transition document, is for
1 microwave hop to fibre which will result in minimal use of 1+1 HSB
configurations. However in the event that this topology is not possible NSI will
implement protection as described above.
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
28/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 28 of 64
2.6.3 Backhaul & Core transmission network dimensioning rules
Forecasting data utilisation across mobile networks is unpredictable due to
the fact that service is quite new and technologies are still evolving. The
dimensioning rules for the core and backhaul networks will be based in the
first instance on projected statistical gain.
To ensure that the Backhaul and Core networks are dimensioned correctly for
the initial network consolidation the following criteria will be used;
Network Statistical gain Action
Backhaul network Less than 6 ok
Greater than 6 and less than 8 under review
8 or greater upgrade
Core Dark Fibre Less than 8 ok
Greater than 8 and less than 10 under review
8 or greater upgrade
The statistical gain will be based on the average throughputs per technology
aggregated. The statistical gain is based on the following calculation;
Stat Gain = Total existing service capacity + Forecasted service capacity
Backhaul capacity
For the backhaul and core networks the current utilisation will be monitored on
a monthly basis with the forecasted Statistical gain forecasted over an annual
basis. This will give rise to programmed capacity upgrades across the
Backhaul (managed and self build) and Core networks. The time to upgrade
trunks across these networks is typically between 6 and 24 months depending
on the upgrade involved.
To facilitate this process the parent companies must provide 12, 24 and 36
month rolling forecasts at least twice yearly. These forecasts must detail at a
minimum;
Volume deployment per service type per geographic area
Average throughput per service type
Max allowable latency per service type
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
29/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 29 of 64
NSI will constantly monitor utilisation Vs forecast and feedback to the parent
companies. This will ensure that the capacity forecasting processes are
optimised over time.
2.6.4 Traffic engineering
As described in section 2.6.2, while all efforts will be made to ensure
congestion and contention is minimised across the transmission network, in
some cases it will be unavoidable. NSI must ensure, in such circumstances,
that both operators have equal access to the available bandwidth. To ensure
that this is the case traffic engineering must be employed across the
transmission and RAN networks;
QoS mapping
Shaping
Policing
Queue management
Quality of service is used to assign priority to certain services above others.
Critical service signalling and GBR services will be assigned the highest
priorities with VBR services assigned lower priority based on the service
and/or the technology. There are large variations in the bandwidth
requirements for LTE, HSPA, R99 and GPRS. For this reason, if all services
were assigned equal priority, during periods of congestion, the low bandwidth
services would be disproportionally impacted to such an extent that they may
become unusable. For that reason, the low bandwidth data services will be
assigned a higher priority to those presenting very high bandwidths.
QoS along with the queue management function should be designed to
ensure, during periods of congestion, that equivalent services from the two
operators have equal access to the available bandwidth.
Table 5 details the proposed QoS mapping for all mobile RAN services.
Traffic Type DSCP L2-pbit MPLS Queue
Signalling, synchronisation, routing
protocols,
24,40,48,49,56 7 CS7 (Strict)
Speech 46 6 EF (Strict)
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
30/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 30 of 64
VBR Streaming, GPRS data,
Gaming
32,34,36,38 4 AF4 (WRED)
R99 data 24,26,28,30 3 AF3 (WRED)
HS Data 18,20,22 2 AF2 (WRED)Premium Internet access 10 1 AF1 (WRED)
LTE Data 0,8 0 BE
Table 5 Quality of Service mapping
Traffic engineering across the IP/MPLS network
Classification
EF
Tail drop
RT
Tail drop
pG
WRED
BE
WRED
Shaper
CIR / PIR
Strict
priority
WFQ
Ingress from Core Traffic
ClassificationQueue &
Queue ManagementShaping Scheduling Trunk Interface
IP/MPLS traffic Engineering
IP Flow
IP Flow
IP Flow
IP Flow
Ingress - POC 1 Location IP/MPLS PHB
G+E
WRED
Shaper
CIR / PIR
Shaping
Figure 10I P/MPLS traff ic engineeri ng
Figure 10 describes the flow of traffic through the IP/MPLS network. On
ingress from the core and access networks traffic is classified according to the
DSCP value and mapped to the required Per Hop Behaviour (PHB) service
class. From there it is passed to the egress interface where it is queued and
scheduled based on a strict plus weighted fair queue (WFQ) mechanism.
GBR services are passed to the strict queue and VBR services are passed to
a weighted fair queue where access to the egress interface is controlledbased on the service class priority. In times of no congestion all traffic is
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
31/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 31 of 64
passed without delay. In a congested environment, GBR services are passed
directly to the egress interface and the VBR services are queued with access
to the egress interface controlled by the weighted fair algorithm. Weighted
Random Early Discard (WRED) is used to ensure efficient queue
management. Packets from data flows are discarded at a pre-determined rate
as the queue fills up. By doing this the 3G flow control and TCP/IP flow control
should slow down resulting in reduced retransmissions and more efficient use
of the available bandwidth.
For enterprise services, policing on ingress will be implemented to ensure the
enterprise customer is within the SLA. In such circumstances a CIR and PIR
can be allocated to the customer services with a CBS and PBS assigned also.
In this case the two rate three colour marking (trTCM) mechanism will be used
to control the flow of enterprise traffic through the network.
Figure 11Enterpri se traff ic engineering
Traffic within contract and within the PBS will be marked Green, traffic greater
than the CIR and within the PIR including the PBS will be marked Yellow, all
other traffic will be marked Red and discarded. In congestion scenarios the
WRED queue management function will discard the Yellow marked packets
first.
Traffic engineering across the Layer 2 Microwave network
Input data burst Policing marking Output traffic
Data
Input data burst Policing marking Output trafficInput data burst Policing marking Output traffic
DataData
Discarded
traffic
Discarded
traffic
Yellow marked traffic.
First to be discarded in
case of network congestions
Yellow marked traffic.
First to be discarded in
case of network congestions
Policing implementation according to standard Two Rate Three Color Marker (trTCM)
CBS allows to tolerate bursts above CIR
short bursts will be marked GREEN
PBS allows to tolerate bursts above PIR
short bursts will not be discarded
Policing implementation according to standard Two Rate Three Color Marker (trTCM)
CBS allows to tolerate bursts above CIR
short bursts will be marked GREEN
PBS allows to tolerate bursts above PIR
short bursts will not be discarded
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
32/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 32 of 64
Across the microwave network a combination of Shaping, CoS based policing,
trTCM and WRED queue management should be used to ensure congestion
control and fairness in terms of bandwidth contention.
For downlink traffic, the physical interface from the IP/MPLS network must be
shaped to the maximum bandwidth of the radio interface. This is to ensure
that egress buffer overflow is not experienced, in particular for large bursts of
LTE traffic. For LTE traffic, shaping per VLAN should also be implemented to
ensure that tail links, which may be connected to feeder links and be of lower
capacity, do not experience buffer overflow.
Note: VLAN shaping for LTE must be considered when considering the Layer
2 VLAN structure and Layer 3 addressing to the H3G LTE network.
Figure 12Downlink tr aff ic control mechanism
For uplink traffic, shaping should be applied on both the H3G and VFI RAN
nodes. This is to ensure that both operators present the same bandwidth to
the Transmission network for sharing.
Data traffic should be policed on ingress to the access microwave network on
a per service level. This ensures that during congestion, out of policy traffic
from each operator is discarded first during periods of congestion.
GE
BEP1.0
LTE
3G
2GBEP2.0
BEP2.0
H3G
VFIE
LTE traffic shaping per service
& per port (VLAN group) shaping
In order to avoid BEP2.0 buffer overflow
Sh
ap
ing
Sh
ap
ing
GE
BEP1.0
LTE
3G
2G
LTE
3G
2GBEP2.0
BEP2.0
H3G
VFIE
LTE traffic shaping per service
& per port (VLAN group) shaping
In order to avoid BEP2.0 buffer overflow
LTE traffic shaping per service
& per port (VLAN group) shaping
In order to avoid BEP2.0 buffer overflow
Sh
ap
ing
Sh
ap
ing
Sh
ap
ing
Sh
ap
ing
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
33/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 33 of 64
As detailed in previous sections the target bandwidth for RBS sites is 400Mb\s
in the City areas, 300Mb\s in towns and 200Mb\s for all others. Tables 6 and 7
detail the proposed policing settings for the two areas.
Data traffic CIR
(Per operator)
PIR
(Per Operator)
Comments
GBR Services NA NA No Policing - Green
GPRS Data 1Mb\s Not set PIR will not be greater than
max link capacity.
Out of policy = yellow
R99 Data 2Mb\s Not set PIR will not be greater than
max link capacity.
Out of policy = yellow
HSDPA 15Mb\s Not Set PIR will not be greater than
max link capacity.
Out of policy = yellow
LTE 20Mb\s 400Mb\s Contracted SLA to operator.
Out of policy = Red
Table 6 City Area (Max link capacity = 400Mb\s)
Traffic CIR
(Per operator)
PIR
(Per Operator)
Comments
GBR Services NA NA No Policing - Green
GPRS Data 1Mb\s Not set
PIR will not be greater than
max link capacity.
Out of policy = yellow
R99 Data 2Mb\s Not set
PIR will not be greater than
max link capacity.Out of policy = yellow
HSDPA 15Mb\s Not Set
PIR will not be greater than
max link capacity.
Out of policy = yellow
LTE 20Mb\s 200Mb\sContracted SLA to operator.
Out of policy = Red
Table 7 Non City Area (Max link capacity = 200Mb\s)
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3
34/64
Transmission network planning__________________________________________________________________________
Transmission network design
& architecture guidelines 13/06/2013 Page 34 of 64
All packets within CIR and the CBS will be marked green. For 3G and HS
services the PIR should not exceed the available link capacity so packets will
be marked as yellow. For LTE traffic, out of policy traffic will be marked red
and discarded.
In some cases the sum of both operators PIR will be greater than the
available link capacity, even at maximum modulation. In this case, it will be
possible for both operators to peak to the maximum available capacity, but not
at the same time.
Figure 13- Normal li nk operation
Figure 13 details the operation of both policing and queue management on a
microwave link. For operator 1, when the traffic presented exceeds the PIR, it
is marked Red and discarded. Where the sum of both operators traffic does
not exceed the interface PIR but exceeds the available link capacity the
WRED mechanism in the outbound queue will start discarding yellow marked
packets at a predetermined rate based on the queue size. In this instance, the
3G flow control and TCP/IP (LTE) flow control mechanisms will slow down the
Policing will color
packets according
to trTCM
CIR1
Operator 1
Operator 2
PIR1
PIR2
CIR2
TX link
capacity
Discarded traffic by policing
Op1 + Op2 traffic exceeding TX link capacity. When queues start to fill-up
WRED (QoS) mechanism will start dropping YELLOW marked packets from data traffic
3G flow control & TCP/IP LTE sessions will slow down traffic of both Operators
Thus preserving GREEN packets (CIR) for both operators
Policing will color
packets according
to trTCM
Policing will color
packets according
to trTCM
CIR1
Operator 1
Operator 2
PIR1
PIR2
CIR2
TX link
capacity
Discarded traffic by policingDiscarded traffic by policing
Op1 + Op2 traffic exceeding TX link capacity. When queues start to fill-up
WRED (QoS) mechanism will start dropping YELLOW marked packets from data traffic
3G flow control & TCP/IP LTE sessions will slow down traffic of both Operators
Thus preserving GREEN packets (CIR) for both operators
Op1 + Op2 traffic exceeding TX link capacity. When queues start to fill-up
WRED (QoS) mechanism will start dropping YELLOW marked packets from data traffic
3G flow control & TCP/IP LTE sessions will slow down traffic of both Operators
Thus preserving GREEN packets (CIR) for both operators
-
7/27/2019 Transmission Network Design and Architecture Guidelines Version 1 3