2 Replies Latest reply: Sep 13, 2017 3:56 AM by Paul Conway RSS

IS-IS Mapping of TLV Codes to enum IsisT_TLV_Type

Paul Conway

I am learning IS-IS and trying to validate Modeler's implementation.  A key point of confusion is the following table.  Can anyone verify the accuracy of the mapping?

 

TLV enumIS-IS TLVsIIH PDULS PDUSN PDUValue
Area Addresses = 01YesYesNoList of Area Id
IS Neighbors6, 2, 22LAN(6)Yes(2, 22)NoList of System Neighbor
IP Int Reachability128NoYesNoList of IP Int Reach Info
IP Ext Reachability130NoLevel 2NoList of IP Int Reach Info
IP Intf Addresses132YesYesNoList of IpT Address
LSP Entries9NoNoYesList of LSP Entry
TE RID134NoYesNoRouter Id TLV
IIH MT129, 143Yes---NoMT Info
LSP MT129, 131, 144---YesNoMT Info
IS IPv6 Neighbors6, 2, 22LAN(6)Yes(2, 22)NoList of System Pv6 Neighbor
Ext Reachable IPv6236NoYesNoList of IPv6 Reach Info
Int Reachable IPv6236NoYesNoList of IPv6 Reach Info
IIH IPv6 Intf Addresses232YesYesNoInetT Address

 

It appears that Support for Extended IP Reachability (135) has been coded, but does not appear to be fully implemented.

 

It appears the following TLVs are implemented in Juniper/Cisco but not in Modeler:  Padding (8), Authentication (10), Checksum (12), Dynamic Hostname (137), MT IS Reachability (222), MT (229), MT IP Reachability (235), and P2P Adjacency (240).

 

I understand that Extended IS Reachability (22) replaces IS Neighbors (2), according to RFC 5305.  Do real routers include both (for backward compatibility) or has it truly been replaced?

 

Note:  Many of the above TLV codes are from recent (post 2000) Standard Track RFCs.  I understand that Riverbed only references ISO 10589, RFC 1195, and a draft TE Extensions (early RFC 5305), so the model may not reflect modern switch and router capabilities.  The model guide includes the following:  "Some IS-IS parameters are not yet modeled.  These will be implemented and documented in upcoming releases."