Linux, FreeBSD, Juniper, Cisco / Network security articles and troubleshooting guides

[b]Example of BGP update message sent from Junos for a VPLS circuit[/b]

Note the use of the BGP extended target communities

[code]Border Gateway Protocol - UPDATE Message
Marker: ffffffffffffffffffffffffffffffff
Length: 88
Type: UPDATE Message (2)
Unfeasible routes length: 0 bytes
Total path attribute length: 65 bytes
Path attributes
ORIGIN: IGP (4 bytes)
Flags: 0x40 (Well-known, Transitive, Complete)
Type code: ORIGIN (1)
Length: 1 byte
Origin: IGP (0)
AS_PATH: empty (3 bytes)
Flags: 0x40 (Well-known, Transitive, Complete)
Type code: AS_PATH (2)
Length: 0 bytes
AS path: empty
LOCAL_PREF: 100 (7 bytes)
Flags: 0x40 (Well-known, Transitive, Complete)
Type code: LOCAL_PREF (5)
Length: 4 bytes
Local preference: 100
EXTENDED_COMMUNITIES: (19 bytes)
Flags: 0xc0 (Optional, Transitive, Complete)
Type code: EXTENDED_COMMUNITIES (16)
Length: 16 bytes
Carried Extended communities
two-octet AS specific Route Target: 64512:10
Layer 2 Information: Unknown, Control Flags: none, MTU: 0 bytes
Encapsulation: Unknown
Control Flags: Control Word not required, Sequenced delivery not required
MTU: 0 bytes
MP_REACH_NLRI (32 bytes)
Flags: 0x90 (Optional, Non-transitive, Complete, Extended Length)
Type code: MP_REACH_NLRI (14)
Length: 28 bytes
Address family: Layer-2 VPN (25)
Subsequent address family identifier: VPLS (65)
Next hop network address (4 bytes)
Subnetwork points of attachment: 0
Network layer reachability information (19 bytes)
RD: 172.16.2.2:10, CE-ID: 11, Label-Block Offset: 9, Label-Block Size: 8, Label Base 262145 (bottom)[/code]