1. MACCS Comms Review – 15 December 2004 Page 1 SRI International MACCS Communications Network Status Review Roy Stehle SRI International Center for GeoSpace Studies Menlo Park, CA 94025 roy.stehle@sri.com 650-859-2552 15 December 2004

2. MACCS Comms Review – 15 December 2004 Page 2 SRI International Agenda o Design Overview o Sample Data Set o View Hardware o Discussion Items

3. MACCS Comms Review – 15 December 2004 Page 3 SRI International MACCS Remote Site Hardware o Computer – 850 MHz Celeron, 256-MB RAM, 80-GB hard drive, Floppy, CD-RW, Linux o NAL Research A3LA-I Iridium Transceiver o Trimble ACE-III GPS Module o NAROD Magnetometer Interface

4. MACCS Comms Review – 15 December 2004 Page 4 SRI International Network Architecture o Remote MACCS sites share a DoD Iridium channel o Data Transport Net Server at SRI manages the link and newsgroup data distribution; generates HTTP status pages and e-mail distribution o Newsgroup data replicated to alternate sites (e.g., Augsburg College, Boston University) Internet Local News Server MACCS-1 MACCS-2 SRI’s News Server

5. MACCS Comms Review – 15 December 2004 Page 5 SRI International Iridium Link Timeshare o Iridium link acquisition: 0.25 to 1.7 sec o Data transfer: 20 to 80 sec –bzip2 compression of data o Nominal data latency: < 5 sec o Link back-off strategy for difficult channels o Host at SRI sets channel transmission strategy MACCS-1 MACCS-2 0 864210 min Link Handshake Data Transfer

6. MACCS Comms Review – 15 December 2004 Page 6 SRI International Data Transfers as Usenet Message Attachments o Well developed protocols for reliable message transfer over a wide variety of networks o Headers provide the metadata; content can be any type of data

7. MACCS Comms Review – 15 December 2004 Page 7 SRI International Newsgroup Message Queue o Remote device writes data files to shared network folder o Posting program reacts to network characteristics o Newsgroup acts as a queue to hold messages –Multiple newsgroups can be handled

8. MACCS Comms Review – 15 December 2004 Page 8 SRI International Newsgroup Publication and Subscription o Single producer, many consumers o Short-term history with automatic expiration o Archive possible at master or at image sites o Data interpretation for quick-look display o Status monitor with distribution of Alerts through e-mail distribution

9. MACCS Comms Review – 15 December 2004 Page 9 SRI International Multisite Data Processing o SRI server can aggregate data from multiple sites (e.g., MACCS-1, MACCS-2)

10. MACCS Comms Review – 15 December 2004 Page 10 SRI International Distribution to Remote News Servers o Periodic replication of data to one or more remote servers (e.g., Augsburg College, Boston University) o Local file access, with access controls, avoids Internet delays o Data replication and archival o Bidirectional

11. MACCS Comms Review – 15 December 2004 Page 11 SRI International Directory of Data Files o File name format: YYYYMMDD-HHMMSS.[hi|lo]res.dat # ll data/ total 184K drwxr-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

12. MACCS Comms Review – 15 December 2004 Page 12 SRI International High-resolution Data Sample o GPS Timestamp –Every 0.5 sec o Data samples (3-axis) # tail -f data/20041206-172500.hires.dat 2004-12-06 17:27:38.02 642671 277214 215738 2004-12-06 17:27:38.52 642573 277209 215701 2004-12-06 17:27:39.02 642597 277230 215742 2004-12-06 17:27:39.52 642633 277203 215717 2004-12-06 17:27:40.02 642559 277227 215719 2004-12-06 17:27:40.52 642703 277195 215724 2004-12-06 17:27:41.02 642515 277226 215716 2004-12-06 17:27:41.52 642706 277201 215732 2004-12-06 17:27:42.02 642548 277222 215716 2004-12-06 17:27:42.52 642663 277209 215732 2004-12-06 17:27:43.02 642596 277223 215733 2004-12-06 17:27:43.52 642612 277217 215716 2004-12-06 17:27:44.02 642683 277212 215735 2004-12-06 17:27:44.52 642587 277219 215703

13. MACCS Comms Review – 15 December 2004 Page 13 SRI International Low-resolution Data Sample # tail -f data/20041214-211000.lores.dat 2004-12-14 21:10:00.00 638511 277690 234520 2004-12-14 21:10:05.00 638504 277698 234518 2004-12-14 21:10:10.00 638514 277697 234516 2004-12-14 21:10:15.00 638537 277693 234513 2004-12-14 21:10:20.00 638574 277673 234511 2004-12-14 21:10:25.00 638576 277667 234509 2004-12-14 21:10:30.00 638528 277680 234506 2004-12-14 21:10:35.00 638425 277710 234504 2004-12-14 21:10:40.00 638549 277671 234502 2004-12-14 21:10:45.00 638548 277666 234499 2004-12-14 21:10:50.00 638542 277668 234497 2004-12-14 21:10:55.00 638575 277673 234495 2004-12-14 21:11:00.00 638537 277697 234492 2004-12-14 21:11:05.00 638533 277687 234490 2004-12-14 21:11:10.00 638539 277677 234488 2004-12-14 21:11:15.00 638534 277680 234485 2004-12-14 21:11:20.00 638545 277687 234483 2004-12-14 21:11:25.00 638568 277674 234480 2004-12-14 21:11:30.00 638583 277661 234478 2004-12-14 21:11:35.00 638469 277699 234476 2004-12-14 21:11:40.00 638551 277675 234473 2004-12-14 21:11:45.00 638556 277677 234471 2004-12-14 21:11:50.00 638545 277682 234469 2004-12-14 21:11:55.00 638542 277684 234466 2004-12-14 21:12:00.00 638534 277692 234464 2004-12-14 21:12:05.00 638525 277698 234462 2004-12-14 21:12:10.00 638524 277697 234459 2004-12-14 21:12:15.00 638518 277704 234457 2004-12-14 21:12:20.00 638515 277707 234455 2004-12-14 21:12:25.00 638506 277701 234452 2004-12-14 21:12:30.00 638485 277709 234450 2004-12-14 21:12:35.00 638380 277748 234448 2004-12-14 21:12:40.00 638476 277716 234445 2004-12-14 21:12:45.00 638492 277711 234443 2004-12-14 21:12:50.00 638493 277711 234441 2004-12-14 21:12:55.00 638500 277708 234438 2004-12-14 21:13:00.00 638504 277711 234436 2004-12-14 21:13:05.00 638504 277718 234434 2004-12-14 21:13:10.00 638509 277712 234431 2004-12-14 21:13:15.00 638513 277706 234429 2004-12-14 21:13:20.00 638513 277694 234427 2004-12-14 21:13:25.00 638508 277698 234424 2004-12-14 21:13:30.00 638492 277702 234422 2004-12-14 21:13:35.00 638383 277738 234420 2004-12-14 21:13:40.00 638482 277710 234417 2004-12-14 21:13:45.00 638499 277707 234415 2004-12-14 21:13:50.00 638498 277707 234413 2004-12-14 21:13:55.00 638501 277707 234410 2004-12-14 21:14:00.00 638500 277707 234408 2004-12-14 21:14:05.00 638493 277707 234406 2004-12-14 21:14:10.00 638504 277701 234403 2004-12-14 21:14:15.00 638499 277706 234401 2004-12-14 21:14:20.00 638500 277708 234399 2004-12-14 21:14:25.00 638488 277716 234396 2004-12-14 21:14:30.00 638488 277705 234394 2004-12-14 21:14:35.00 638378 277740 234392 2004-12-14 21:14:40.00 638492 277705 234389 2004-12-14 21:14:45.00 638509 277709 234387 2004-12-14 21:14:50.00 638524 277704 234385 2004-12-14 21:14:55.00 638520 277711 234383

14. MACCS Comms Review – 15 December 2004 Page 14 SRI International Iridium and Ethernet Network Routing Tables # sudo /sbin/ifup iridium # netstat -rn Kernel IP routing table Destination Gateway Genmask Flags MSS Window irtt Iface 128.18.26.43 0.0.0.0 255.255.255.255 UH 0 0 0 ppp0 192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0 169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eth0 0.0.0.0 128.18.26.43 0.0.0.0 UG 0 0 0 ppp0 # sudo /sbin/ifdown iridium # netstat -rn Kernel IP routing table Destination Gateway Genmask Flags MSS Window irtt Iface 192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0 169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eth0 0.0.0.0 192.168.1.1 0.0.0.0 UG 0 0 0 eth0 # ping fireball.sri.com PING 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 ms 64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=1 ttl=63 time=0.745 ms 64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=2 ttl=63 time=0.757 ms

15. MACCS Comms Review – 15 December 2004 Page 15 SRI International Iridium 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)

16. MACCS Comms Review – 15 December 2004 Page 16 SRI International Iridium Network Ping Statistics # ping fireball.sri.com PING 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 ms 64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=1 ttl=63 time=4230 ms 64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=2 ttl=63 time=3395 ms 64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=3 ttl=63 time=2581 ms 64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=4 ttl=63 time=2404 ms 64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=5 ttl=63 time=2289 ms 64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=6 ttl=63 time=2350 ms 64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=7 ttl=63 time=2333 ms 64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=8 ttl=63 time=2415 ms 64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=9 ttl=63 time=2402 ms 64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=10 ttl=63 time=2303 ms 64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=11 ttl=63 time=2291 ms 64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=12 ttl=63 time=2375 ms 64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=13 ttl=63 time=2359 ms 64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=14 ttl=63 time=2443 ms 64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=15 ttl=63 time=2337 ms 64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=16 ttl=63 time=2333 ms 64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=17 ttl=63 time=2407 ms 64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=18 ttl=63 time=4800 ms 64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=19 ttl=63 time=3897 ms 64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=20 ttl=63 time=2987 ms 64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=21 ttl=63 time=2339 ms 64 bytes from fireball.SRI.COM (128.18.26.41): icmp_seq=22 ttl=63 time=2325 ms 64 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 32951ms rtt min/avg/max/mdev = 2289.599/2798.130/5135.301/828.190 ms, pipe 7

17. MACCS Comms Review – 15 December 2004 Page 17 SRI International Items for Discussion o Schedule –Student visit –Shipment to Boston University –Field deployment o SRI as Prime News Host –Network monitoring –E-mail alerts o Data archival –Researcher responsibility –Local news aging o Difficult link management strategy –Latency requirements –Need for low resolution data o CD burning at remote sites –Is it needed if data verified after receipt over Iridium?