Packet Captures
BGP_MP_NLRI.cap 2.9 KB
Submitted Jun 28, 2010
IPv6 routes are carried as a separate address family inside MP_REACH_NLRI attributes.
| Packets: 24 | Duration: 60s | Downloads: 16615 |
TCP_SACK.cap 27.5 KB
Submitted Jun 16, 2010
A TCP SACK option is included in packets #31, #33, #35, and #37. The missing segment is retransmitted in packet #38.
| Packets: 39 | Duration: n/a | Downloads: 26834 |
4-byte_AS_numbers_Mixed_Scenario.cap 414 bytes
Submitted Apr 30, 2010 by pierky
Router "B" (AS 2) at 172.16.3.2 does not support 4-byte AS numbers, while router "A" (AS 10.1 / 655361) at 172.16.3.1 does.
Router "A" receives an UPDATE for the 40.0.0.0/8 subnet from an external router ("D") in the AS 40.1 / 2621441 (not shown), and it forwards it to "B" (pkt n. 2): AS_PATH contains "23456 23456" (the first stands for AS 10.1, the second for the originating AS 40.1), but NEW_AS_PATH contains the real 4-byte AS numbers.
At pkt n. 3 "B" receives the same subnet directly from "D" and sends it to "A", including the original NEW_AS_PATH attribute previously appended by "D".
| Packets: 4 | Duration: 60s | Downloads: 9551 |
4-byte_AS_numbers_Full_Support.cap 1.2 KB
Submitted Apr 30, 2010 by pierky
Router at 172.16.1.2 (hostname "D", AS 40.1 / 2621441) clears a previous established peering with 172.16.1.1 (hostname "A", AS 10.1 / 655361); They both support 32-bit ASN.
While opening the new session, they negotiate the "Four-octet AS Number Capability" (pkts n. 2 and 3).
Then, both "A" and "D" send some UPDATEs containing 4-octect encoded AS_PATH attributes (pkts n. 6 and 9). Please note: WireShark may show wrong paths unless you force 4-byte encoding in the Preferences / Protocols / BGP options.
| Packets: 9 | Duration: 56s | Downloads: 8906 |
LDP_Ethernet_FrameRelay.pcap.cap 2.1 KB
Submitted Dec 5, 2009 by pierky
LDP with pseudowire FEC elements (Ethernet and Frame-Relay DLCI-to-DLCI)
| Packets: 14 | Duration: 7s | Downloads: 9652 |
BGP_MD5.cap 1.7 KB
Submitted Nov 26, 2009
An EBGP with TCP MD5 authentication enabled
| Packets: 16 | Duration: 61s | Downloads: 10882 |
BGP_redist.cap 378 bytes
Submitted Oct 28, 2009 by colinbsd
The OSPF metric is preserved and propagated within the MPLS cloud by the MP-BGP MED attribute.
| Packets: 2 | Duration: n/a | Downloads: 10068 |
EoMPLS.cap 7.0 KB
Submitted Oct 12, 2009 by pierky
Routers at 1.1.2.1 and 1.1.2.2 are PEs in a MPLS cloud. LDP starts at packet 8 and they build up a pseudo-wire VC (last FEC in packets 11 and 13). At packet 15 we already have STP running between CE1 and CE2 (two routers with ESW), encapsulated in 2 MPLS headers. All the ethernet stuff follows: CDP, ARP, ICMP between two hosts on the same subnet.
| Packets: 56 | Duration: 32s | Downloads: 11498 |
telnet.cap 9.4 KB
Submitted Sep 14, 2009
Telnetting from one router to another. Note that all communication is visible in clear text.
| Packets: 74 | Duration: 10s | Downloads: 10029 |
TDP.cap 2.8 KB
Submitted Sep 14, 2009
P2 and PE2 exchange Tag Distribution Protocol hellos and form an adjacency over TCP port 711.
| Packets: 33 | Duration: 47s | Downloads: 6408 |
SSHv2.cap 11.4 KB
Submitted Sep 14, 2009
An SSH version 2 session between two routers. All communication is securely encrypted.
| Packets: 90 | Duration: 7s | Downloads: 45567 |
PPP_TCP_compression.cap 1.5 KB
Submitted Sep 14, 2009
A telnet session is established to 191.1.13.3 across a PPP link performing TCP header compression. The user at 191.1.13.1 logs in with the password "cisco" and terminates the connection.
| Packets: 43 | Duration: 3s | Downloads: 6503 |
MSDP.cap 4.1 KB
Submitted Sep 14, 2009
R2 and R3 become MSDP peers and exchange keepalives. A multicast source 172.16.40.10 begins sending traffic to group 239.123.123.123, and R2 begins sending periodic source active messages to R3. Capture perspective is the R2-R3 link.
| Packets: 35 | Duration: 391s | Downloads: 6326 |
LDP_adjacency.cap 5.7 KB
Submitted Sep 14, 2009
PE1 and P1 multicast LDP hellos to 224.0.0.2 on UDP port 646. They then establish an adjacency on TCP port 646 and exchange labels.
| Packets: 61 | Duration: 108s | Downloads: 9751 |
IBGP_adjacency.cap 2.3 KB
Submitted Sep 14, 2009
Routers 3 and 4 form an internal BGP relationship. This is evidenced by the OPEN messages in packets #4 and #5, which show both routers belong to the same AS (65300). Also note that IBGP packets are not subject to a limited TTL as are EBGP packets.
| Packets: 17 | Duration: 63s | Downloads: 7940 |
EBGP_adjacency.cap 2.7 KB
Submitted Sep 14, 2009
The external BGP adjacency between routers 1 and 2 is brought online and routes are exchanged. Keepalives are then exchanged every 60 seconds. Note that the IP TTL (normally 1) has been increased to 2 with ebgp-multihop to facilitate communication between the routers' loopback interfaces.
| Packets: 24 | Duration: 182s | Downloads: 8162 |
BGP_soft_reset.cap 2.0 KB
Submitted Sep 14, 2009
R1 performs a soft bidirectional reset (clear ip bgp soft) on its adjacency with R2. The ROUTE-REFRESH message is visible in packet #7. Note that the TCP connection remains uninterrupted, and neither router views the reset as disruptive.
| Packets: 17 | Duration: 180s | Downloads: 6761 |
BGP_notification.cap 764 bytes
Submitted Sep 14, 2009
R1 has been misconfigured to expect R2 to reside in AS 65100. R2 attempts to peer with R1 advertising itself correctly in AS 65200. R1 issues a NOTIFICATION in packet #5 citing a "bad peer AS" error and terminates the TCP connection.
| Packets: 9 | Duration: n/a | Downloads: 7022 |
BGP_hard_reset.cap 3.2 KB
Submitted Sep 14, 2009
A hard reset (clear ip bgp) is performed on R1 for its adjacency with R2. Packet #7 shows R1 sending a packet with the TCP FIN flag set, indicating the connection is to be torn down. The TCP connection is then reestablished and UPDATEs are retransmitted.
| Packets: 32 | Duration: 208s | Downloads: 6656 |
BGP_AS_set.cap 1.6 KB
Submitted Sep 14, 2009
Packet #15 includes a BGP update containing both an AS sequence and an AS set in its AS path attribute.
| Packets: 18 | Duration: 1s | Downloads: 7991 |