Netgear XSM4348CS User Manual - Page 381

M4300 Intelligent Edge Series Fully Managed Stackable Switches Table 136. OSPF Link State Database (continued) Field LSA Type LS ID Age Sequence Checksum Options Description The format and function of the link state advertisement. LSA Type is one of the following: • Illegal • Router Links • Network Links • Network Summary • ASBR Summary • AS-external • Group Member • NSSA • TMP2 • Link Opaque • Area Opaque • AS Opaque • Unknown The link state ID identifies the piece of the routing domain that is being described by the advertisement. The value of the LS ID depends on the advertisement's LS type. The time since the link state advertisement was first originated, in seconds. The sequence number field is a signed 32-bit integer. It is used to detect old and duplicate link state advertisements. The larger the sequence number, the more recent the advertisement. The checksum is used to detect data corruption of an advertisement. This corruption can occur while an advertisement is being flooded, or while it is being held in a router's memory. This field is the checksum of the complete contents of the advertisement, except the LS age field. The Options field in the link state advertisement header indicates which optional capabilities are associated with the advertisement. The options are as follows: • Q. This enables support for QoS traffic engineering. • E. This describes the way AS external LSAs are flooded. • MC. This describes the way IP multicast datagrams are forwarded according to the standard specifications. • O. This describes whether opaque LSAs are supported. • V. This describes whether OSPF++ extensions for VPN/COS are supported. Configure OSPF and OSPFv3 381 User Manual