|
Previous
|
Content
|
Next
|
|
|
|
| OSPF requires the following pieces of
system support: |
| Timers |
| |
Two different kind of timers are required. Single
shot timers fire once and cause a protocol event to be processed.
Interval timers fire at continuous intervals. These are used for the
sending of packets at regular intervals. |
|
|
| IP Multicast |
| |
Support for receiving and sending IP multicast
datagrams, along with the appropriate lower-level protocol support,
is required. The IP multicast datagrams never travel more than
one hop. |
|
|
| Variable-length subnet support |
| |
The router's IP protocol must support
variable-length subnetting. |
|
|
| IP supernetting support |
| |
The router's IP protocol must support IP
supernetting. |
|
|
| Lower-level protocol support |
| |
Lower-level protocol must have some way of
indication when an interface goes up and down. |
|
|
|
Non-broadcast lower-level protocol support |
| |
On non-broadcast networks lower-level protocol
support is required to provide an indication when an attempt in made to
send a packet to a dead on non-existing router. |
|
|
|
List manipulation primitives |
| |
Much of the OSPF functionality is described in
terms of its operation on lists of LSAs. An OSPF
implementation needs to be able to manipulate these lists, adding and
deleteing constituent LSAs as necessary. |
|
|
|
Tasking support |
| |
Certain OSPF procedures invoke other procedures.
At times, these other procedures should be executed in-line, that
is, before the current procedure is finished. At other times, the other
procedures are to be executed only when the current procedure has
finished. |
|
|
|
Previous
|
Content
|
Next
|