Is-Is Pdus - HP 5500 EI series Configuration Manual

Hide thumbs Also See for 5500 EI series:
Table of Contents

Advertisement

NOTE:
On an IS-IS broadcast network, all routers establish adjacency relationships, but they synchronize their
LSDBs through the DIS.

IS-IS PDUs

PDU
IS-IS PDUs are encapsulated into link layer frames. An IS-IS PDU has two parts, the headers and the
variable length fields. The headers comprise the PDU common header and the PDU specific header. All
PDUs have the same PDU common header. The specific headers vary by PDU type.
Figure 36 PDU format
Table 4 PDU types
Type
15
16
17
18
20
24
25
26
27
Hello PDU
IS-to-IS hello (IIH) PDUs are used by routers to establish and maintain neighbor relationships. On
broadcast networks, Level- 1 routers use Level- 1 LAN IIHs, and Level-2 routers use Level-2 LAN IIHs. The
P2P IIHs are used on point-to-point networks.
LSP
The LSPs carry link state information. LSPs include Level- 1 LSPs and Level-2 LSPs. The Level-2 LSPs are sent
by the Level-2 routers, and the Level- 1 LSPs are sent by the Level- 1 routers. The Level- 1 -2 router can send
both types of LSPs.
SNP
A sequence number PDU (SNP) describes the complete or partial LSPs for LSDB synchronization.
SNPs include CSNP and PSNP, which are further divided into Level- 1 CSNP, Level-2 CSNP, Level- 1 PSNP,
and Level-2 PSNP.
PDU Type
Level-1 LAN IS-IS hello PDU
Level-2 LAN IS-IS hello PDU
Point-to-Point IS-IS hello PDU
Level-1 Link State PDU
Level-2 Link State PDU
Level-1 Complete Sequence Numbers PDU
Level-2 Complete Sequence Numbers PDU
Level-1 Partial Sequence Numbers PDU
Level-2 Partial Sequence Numbers PDU
127
Acronym
L1 LAN IIH
L2 LAN IIH
P2P IIH
L1 LSP
L2 LSP
L1 CSNP
L2 CSNP
L1 PSNP
L2 PSNP

Advertisement

Table of Contents
loading

This manual is also suitable for:

5500 si series

Table of Contents