MACCS Comms Review – 15 December 2004Page 1 SRI International

MACCS Communications Network MACCS Communications Network Status ReviewStatus Review

Roy StehleSRI International

Center for GeoSpace Studies

Menlo Park, CA 94025roy.stehle@sri.com 650-859-2552

15 December 2004

MACCS Comms Review – 15 December 2004Page 2 SRI International

AgendaAgenda

Design Overview

Sample Data Set

View Hardware

Discussion Items

MACCS Comms Review – 15 December 2004Page 3 SRI International

MACCS Remote Site HardwareMACCS Remote Site Hardware

Computer – 850 MHz Celeron, 256-MB RAM, 80-GB hard drive, Floppy, CD-RW, Linux

NAL Research A3LA-I Iridium Transceiver

Trimble ACE-III GPS Module

NAROD Magnetometer Interface

MACCS Comms Review – 15 December 2004Page 4 SRI International

Network ArchitectureNetwork Architecture

Remote MACCS sites share a DoD Iridium channel

Data Transport Net Server at SRI manages the link and newsgroup data distribution; generates HTTP status pages and e-mail distribution

Newsgroup data replicated to alternate sites (e.g., Augsburg College, Boston University)

Internet

Local News Server

MACCS-1

MACCS-2SRI’s News Server

MACCS Comms Review – 15 December 2004Page 5 SRI International

Iridium Link TimeshareIridium Link Timeshare

Iridium link acquisition: 0.25 to 1.7 sec

Data transfer: 20 to 80 sec– bzip2 compression of data

Nominal data latency: < 5 sec

Link back-off strategy for difficult channels

Host at SRI sets channel transmission strategy

MACCS-1

MACCS-20 8642 10 min

Link Handshake

Data Transfer

MACCS Comms Review – 15 December 2004Page 6 SRI International

Data Transfers as Usenet Message AttachmentsData Transfers as Usenet Message Attachments

Well developed protocols for reliable message transfer over a wide variety of networks

Headers provide the metadata; content can be any type of data

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Newsgroup Message QueueNewsgroup Message Queue

Remote device writes data files to shared network folder

Posting program reacts to network characteristics

Newsgroup acts as a queue to hold messages– Multiple newsgroups can be handled

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Newsgroup Publication and SubscriptionNewsgroup Publication and Subscription

Single producer, many consumers

Short-term history with automatic expiration

Archive possible at master or at image sites

Data interpretation for quick-look display

Status monitor with distribution of Alerts through e-mail distribution

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Multisite Data ProcessingMultisite Data Processing

SRI server can aggregate data from multiple sites(e.g., MACCS-1, MACCS-2)

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Distribution to Remote News ServersDistribution to Remote News Servers

Periodic replication of data to one or more remote servers(e.g., Augsburg College, Boston University)

Local file access, with access controls, avoids Internet delays

Data replication and archival

Bidirectional

MACCS Comms Review – 15 December 2004Page 11 SRI International

Directory of Data FilesDirectory of Data Files

File name format: YYYYMMDD-HHMMSS.[hi|lo]res.dat

# ll data/total 184Kdrwxr-xr-x 2 transport transport 4.0K Dec 6 17:25 ./drwxr-xr-x 7 transport transport 4.0K Dec 6 17:06 ../-rw-rw-r-- 1 transport transport 26K Dec 6 16:39 20041206-163500.hires.dat-rw-rw-r-- 1 transport transport 2.6K Dec 6 16:40 20041206-163500.lores.dat-rw-rw-r-- 1 transport transport 26K Dec 6 16:44 20041206-164000.hires.dat-rw-rw-r-- 1 transport transport 2.6K Dec 6 16:45 20041206-164000.lores.dat-rw-rw-r-- 1 transport transport 26K Dec 6 16:49 20041206-164500.hires.dat-rw-rw-r-- 1 transport transport 2.6K Dec 6 16:50 20041206-164500.lores.dat-rw-rw-r-- 1 transport transport 26K Dec 6 16:54 20041206-165000.hires.dat-rw-rw-r-- 1 transport transport 2.6K Dec 6 16:55 20041206-165000.lores.dat-rw-rw-r-- 1 transport transport 26K Dec 6 16:59 20041206-165500.hires.dat-rw-rw-r-- 1 transport transport 2.6K Dec 6 17:00 20041206-165500.lores.dat-rw-rw-r-- 1 transport transport 10K Dec 6 17:26 20041206-172500.hires.dat-rw-rw-r-- 1 transport transport 1012 Dec 6 17:26 20041206-172500.lores.dat

MACCS Comms Review – 15 December 2004Page 12 SRI International

High-resolution Data SampleHigh-resolution Data Sample

GPS Timestamp– Every 0.5 sec

Data samples (3-axis)

# tail -f data/20041206-172500.hires.dat2004-12-06 17:27:38.02642671 277214 2157382004-12-06 17:27:38.52642573 277209 2157012004-12-06 17:27:39.02642597 277230 2157422004-12-06 17:27:39.52642633 277203 2157172004-12-06 17:27:40.02642559 277227 2157192004-12-06 17:27:40.52642703 277195 2157242004-12-06 17:27:41.02642515 277226 2157162004-12-06 17:27:41.52642706 277201 2157322004-12-06 17:27:42.02642548 277222 2157162004-12-06 17:27:42.52642663 277209 2157322004-12-06 17:27:43.02642596 277223 2157332004-12-06 17:27:43.52642612 277217 2157162004-12-06 17:27:44.02642683 277212 2157352004-12-06 17:27:44.52642587 277219 215703

MACCS Comms Review – 15 December 2004Page 13 SRI International

Low-resolution Data SampleLow-resolution Data Sample

# tail -f data/20041214-211000.lores.dat2004-12-14 21:10:00.00 638511 277690 2345202004-12-14 21:10:05.00 638504 277698 2345182004-12-14 21:10:10.00 638514 277697 2345162004-12-14 21:10:15.00 638537 277693 2345132004-12-14 21:10:20.00 638574 277673 2345112004-12-14 21:10:25.00 638576 277667 2345092004-12-14 21:10:30.00 638528 277680 2345062004-12-14 21:10:35.00 638425 277710 2345042004-12-14 21:10:40.00 638549 277671 2345022004-12-14 21:10:45.00 638548 277666 2344992004-12-14 21:10:50.00 638542 277668 2344972004-12-14 21:10:55.00 638575 277673 2344952004-12-14 21:11:00.00 638537 277697 2344922004-12-14 21:11:05.00 638533 277687 2344902004-12-14 21:11:10.00 638539 277677 2344882004-12-14 21:11:15.00 638534 277680 2344852004-12-14 21:11:20.00 638545 277687 2344832004-12-14 21:11:25.00 638568 277674 2344802004-12-14 21:11:30.00 638583 277661 2344782004-12-14 21:11:35.00 638469 277699 2344762004-12-14 21:11:40.00 638551 277675 2344732004-12-14 21:11:45.00 638556 277677 2344712004-12-14 21:11:50.00 638545 277682 2344692004-12-14 21:11:55.00 638542 277684 2344662004-12-14 21:12:00.00 638534 277692 2344642004-12-14 21:12:05.00 638525 277698 2344622004-12-14 21:12:10.00 638524 277697 2344592004-12-14 21:12:15.00 638518 277704 2344572004-12-14 21:12:20.00 638515 277707 2344552004-12-14 21:12:25.00 638506 277701 2344522004-12-14 21:12:30.00 638485 277709 234450

2004-12-14 21:12:35.00 638380 277748 2344482004-12-14 21:12:40.00 638476 277716 2344452004-12-14 21:12:45.00 638492 277711 2344432004-12-14 21:12:50.00 638493 277711 2344412004-12-14 21:12:55.00 638500 277708 2344382004-12-14 21:13:00.00 638504 277711 2344362004-12-14 21:13:05.00 638504 277718 2344342004-12-14 21:13:10.00 638509 277712 2344312004-12-14 21:13:15.00 638513 277706 2344292004-12-14 21:13:20.00 638513 277694 2344272004-12-14 21:13:25.00 638508 277698 2344242004-12-14 21:13:30.00 638492 277702 2344222004-12-14 21:13:35.00 638383 277738 2344202004-12-14 21:13:40.00 638482 277710 2344172004-12-14 21:13:45.00 638499 277707 2344152004-12-14 21:13:50.00 638498 277707 2344132004-12-14 21:13:55.00 638501 277707 2344102004-12-14 21:14:00.00 638500 277707 2344082004-12-14 21:14:05.00 638493 277707 2344062004-12-14 21:14:10.00 638504 277701 2344032004-12-14 21:14:15.00 638499 277706 2344012004-12-14 21:14:20.00 638500 277708 2343992004-12-14 21:14:25.00 638488 277716 2343962004-12-14 21:14:30.00 638488 277705 2343942004-12-14 21:14:35.00 638378 277740 2343922004-12-14 21:14:40.00 638492 277705 2343892004-12-14 21:14:45.00 638509 277709 2343872004-12-14 21:14:50.00 638524 277704 2343852004-12-14 21:14:55.00 638520 277711 234383

MACCS Comms Review – 15 December 2004Page 14 SRI International

Iridium and Ethernet Network Routing TablesIridium and Ethernet Network Routing Tables

# sudo /sbin/ifup iridium# netstat -rnKernel IP routing tableDestination Gateway Genmask Flags MSS Window irtt Iface128.18.26.43 0.0.0.0 255.255.255.255 UH 0 0 0 ppp0192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eth00.0.0.0 128.18.26.43 0.0.0.0 UG 0 0 0 ppp0

# sudo /sbin/ifdown iridium# netstat -rnKernel IP routing tableDestination Gateway Genmask Flags MSS Window irtt Iface192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eth00.0.0.0 192.168.1.1 0.0.0.0 UG 0 0 0 eth0

# ping fireball.sri.comPING fireball.sri.com (128.18.26.41) 56(84) bytes of data.64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=0 ttl=63 time=0.811 ms64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=1 ttl=63 time=0.745 ms64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=2 ttl=63 time=0.757 ms

MACCS Comms Review – 15 December 2004Page 15 SRI International

Iridium Network TimingIridium Network Timing

# tail -f link.log[2004-12-15 09:56:34 INFO] LinkControl: Posted link stats[2004-12-15 09:56:34 INFO] LinkControl: Shutting down the link ...[2004-12-15 09:56:51 INFO] LinkControl: Link is down (took 00:00:17.27 to hangup)[2004-12-15 10:00:10 INFO] LinkControl: Bringing up the Iridium link ...[2004-12-15 10:00:50 INFO] LinkControl: Link is up (took 00:00:39.86 to dial)[2004-12-15 10:00:50 INFO] LinkControl: Posting...[2004-12-15 10:01:15 INFO] LinkControl: Transferred 3480 bytes in 24 secs (143.37 bytes/sec[2004-12-15 10:01:15 INFO] LinkControl: Posted link stats[2004-12-15 10:01:15 INFO] LinkControl: Shutting down the link ...[2004-12-15 10:01:22 INFO] LinkControl: Link is down (took 00:00:07.22 to hangup)[2004-12-15 10:05:10 INFO] LinkControl: Bringing up the Iridium link ...[2004-12-15 10:06:34 INFO] LinkControl: Link is up (took 00:01:24.31 to dial)[2004-12-15 10:06:34 INFO] LinkControl: Posting...[2004-12-15 10:07:14 INFO] LinkControl: Transferred 3480 bytes in 40 secs (86.86 bytes/sec[2004-12-15 10:07:14 INFO] LinkControl: Posted link stats[2004-12-15 10:07:14 INFO] LinkControl: Shutting down the link ...[2004-12-15 10:07:22 INFO] LinkControl: Link is down (took 00:00:07.23 to hangup)

MACCS Comms Review – 15 December 2004Page 16 SRI International

Iridium Network Ping StatisticsIridium Network Ping Statistics# ping fireball.sri.comPING fireball.sri.com (128.18.26.41) 56(84) bytes of data.64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=0 ttl=63 time=5135 ms64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=1 ttl=63 time=4230 ms64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=2 ttl=63 time=3395 ms64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=3 ttl=63 time=2581 ms64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=4 ttl=63 time=2404 ms64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=5 ttl=63 time=2289 ms64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=6 ttl=63 time=2350 ms64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=7 ttl=63 time=2333 ms64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=8 ttl=63 time=2415 ms64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=9 ttl=63 time=2402 ms64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=10 ttl=63 time=2303 ms64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=11 ttl=63 time=2291 ms64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=12 ttl=63 time=2375 ms64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=13 ttl=63 time=2359 ms64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=14 ttl=63 time=2443 ms64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=15 ttl=63 time=2337 ms64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=16 ttl=63 time=2333 ms64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=17 ttl=63 time=2407 ms64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=18 ttl=63 time=4800 ms64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=19 ttl=63 time=3897 ms64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=20 ttl=63 time=2987 ms64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=21 ttl=63 time=2339 ms64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=22 ttl=63 time=2325 ms64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=23 ttl=63 time=2412 ms --- fireball.sri.com ping statistics ---26 packets transmitted, 24 received, 7% packet loss, time 32951msrtt min/avg/max/mdev = 2289.599/2798.130/5135.301/828.190 ms, pipe 7

MACCS Comms Review – 15 December 2004Page 17 SRI International

Items for DiscussionItems for Discussion

Schedule– Student visit– Shipment to Boston University– Field deployment

SRI as Prime News Host– Network monitoring– E-mail alerts

Data archival– Researcher responsibility– Local news aging

Difficult link management strategy– Latency requirements– Need for low resolution data

CD burning at remote sites– Is it needed if data verified after receipt over Iridium?