Network Types and Terms

ByBob Larson

Just a Thought

Network Types

LAN – Local Area Network WAN – Wide Area Network Campus Network MAN – Metropolitan Area Network WLAN – Wireless LAN

Local Area Network (LAN)

Connects devices in a limited geographical area Using one or more hubs, switches or wireless access points

Can be quite small – few devices Home network Small Office Home Office (SOHO)

Can be larger – up to thousands of devices LAN Bandwidth determined by devices and connecting media

Typically Ethernet 10/100/1000 Mbps ( 1000 Mb = 1 Gb)

Wide Area Network (WAN)

Links networks or devices over larger geographical area

Across town or across the globe Involves a 3rd-party service provider

Telcos, Cable Companies & Satellite Types of service

Part-time (on demand) MODEM & ISDN – Home and smallest

business Full-time (always-on)

E1/T1/T3 s, Frame Relay – Business Cable and DSL (broadband) - Everyone

Why do we need them Power of Eminent Domain

Connects to LANs using a router

LANs vs WANs

LAN Limited distance Managed by company Connects computers Bandwidth based on

local technology Free after installation Typically very fast

10/100/1000 Mb

WAN Long distance Managed by provider Connects LANs Bandwidth limited by

provider It’s what they sell Higher BW – Higher cost Typically slower than

LAN Often 1.5 Mb or less (T1) 3-45 Mb possible ($$$)

Three LANS Connected by WANs

Internet

LAN 1 LAN 2

LAN 3In each case the router is both part of the LAN and part of the WAN

Your House

My House

The UW or your employer

UUNET’s North America Network

Campus Network Multiple buildings in close proximity

Organization owns or controls the land between buildings Administrators can connect buildings without

using 3rd party service provider Network looks like a large LAN

Buildings connected by high speed links Typically Ethernet (100/1000 Mbps)

Bandwidth cost is basically capital cost of installing the links (like a LAN)

Examples Microsoft – Redmond, WA Cisco Systems – San Jose, CA Any Boeing Plant – Renton, Kent, Auburn, Everett Typical High School or College campus

Metropolitan Area Network (MAN)

Multiple buildings in close proximity Organization doesn’t control the land between

buildings Public streets maybe

Administrators must use 3rd party service provider to connect buildings

Looks more like LANs connected by WANs Because of single provider, may be able to negotiate

lower rates for higher bandwidth Bandwidth cost is monthly expense like WAN Examples

Boeing Puget Sound Facilities (10+ campuses) Typical School District with multiple campuses

WiFi Extending the LAN

Provides user mobility Can be cheaper both short and long term Provides access where copper won’t work

WiFi Linking Sites Together

May replace high cost WAN links Requires unobstructed line-of-site

Topologies

Network Topology

Token RingFDDI

Ethernet orWAN ProtocolsEthernet

Ethernet Ethernet

Ethernet

Old

Old

Full and partial mesh are most common in Man, Campus and WAN implementations. Where high redundancy required.

Cellular Wireless / Topology

Common First Network

Home network to share a printer SOHO or ROBO to share printer and/or files Easy to purchase and setup

Often sold as kits at any computer store Hub/Switch could be replaced with wireless Access Point

(AP)

Adding Internet Access

Home network or small network can share Internet connection

DSL/Cable router with built-in hub/switch & maybe WiFi If there are two different nets inside/outside it is a router

and probably performing NAT and DHCP

Default Gateway

Business Networks

Single-Site Business

Default Gateway

What does a network look like?

Global Networks

WAN Connections

Fin…

Technology is dominated by two types of people: those who understand what they do not manage, and those who manage what they do not understand.~ Source Unknown ~