R3303-HP HSR6800 Routers Layer 3 - IP Routing Configuration Guide

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Figure 42 L1/L2 LSP format
Major fields of the L1/L2 LSP are as follows:
• PDU length—Total length of the PDU in bytes.
• Remaining lifetime—LSP remaining lifetime in seconds.
• LSP ID—Consists of the system ID, the pseudonode ID (one byte) and the LSP fragment number (one
byte).
• Sequence number—LSP sequence number.
• Checksum—LSP checksum.
• P (Partition)—Partition bit that is only for L2 LSPs. This field indicates whether the router supports
partition repair.
• ATT (Attach)—Attach bit that is generated by a L1/L1 router for L1 LSPs only. This field indicates that
the router generating the LSP is connected to multiple areas.
• OL (Overload)—The LSDB is not complete because the router has run out of memory. Other routers
will not send packets to the overloaded router, except packets destined to the networks directly
connected to the router. For example, in Figure 43, R
outer A forwards packets to Router C through
Router B. Once other routers know the OL field of LSPs from Router B is set to 1, Router A will send
packets to Router C through Router D and Router E, but still send to Router B packets destined to the
network directly connected to Router B.
• IS type—Type of the router generating the LSP.