- Recall:
- A ROUTE ERROR message
contains the broken link
- Nodes will cache the broken links reported
- A ROUTE ERROR message
contains the broken link
- Note:
- A broken link
cache entry has
a short time out value
associated with the entry
- When the time expires, the entry is deleted
- The time out is
short because:
- This ad hoc wireless network is very dynamic
If a broken link is "repaired" (node has moved back in range), then:
- The broken link cache entry will refuse to let a node use the fixed link !!!
- A broken link
cache entry has
a short time out value
associated with the entry
- Using the
information on
broken links:
- When a node receives
a ROUTE REPLY:
- The node will reject (= discard) a route that contains a broken link
- When a node receives
a ROUTE REPLY:
- Example:
- Node A
got the broken link CD and
now starts
a Route Discovery:
- Node B
received the ROUTE REQUEST and
decides to
short-circuit the
ROUTE REQUEST with
its route cache:
- Node A will now
reject the
ROUTE REPLY:
because it contains the broken link CS.
- Node A
got the broken link CD and
now starts
a Route Discovery: