How eigrp prevent loop

Question:

in fact i cracked it i think

rtp aids in loop avoidance...as it ensures that each eigrp router releiably receives updates.

if updates were not reliable...then the update may fail to reach the router.

and the router dual process would not process potentially important information that could be missing from the topology table

and hence could come up with substandard routes that could cause loops.

thats how it aids in loop prevention.

case closed.

its a bit embarassing, but i have to say question answered...to let others know question has been answered.

Answer:

RTP per se does not do it, RTP is just the proprietary transport protocol. Dual is the mechanism.

As I understood, RTP by its finctionality can't do anything fo route computation.Loop avoidence in eigrp is achived by the choose of an Successor and FS. But have no idea how it can assure a loop free route because all routers in th AS choose routes independently, unlike OSPF (ospf can assure because dijstra SPF). This may be not in the range of original question.

considering the rule of choosing a route to a subnet "lowest metrric", If an advartisement for a route from a router is coming again to the same router only a route loop could occur. So, in order to prevent the loop there should not be any circles in the path the eigrp update message spreads. As I saw in a book eigrp update messages flow map is a tree of routers. So, the tree model of update message flow is the solution. And this should be the type of functionality RTP adds to the eigrp in order to help prevent loops.

Am I correct? . Or else is there any other protocol or algorhythm (DUAL) doing loop prevention in this way ir another way.?

in fact i cracked it i think

rtp aids in loop avoidance...as it ensures that each eigrp router or 3 layer switch like WS-C3560X-24T-S releiably receives updates.

if updates were not reliable...then the update may fail to reach the router.

and the router dual process would not process potentially important information that could be missing from the topology table

and hence could come up with substandard routes that could cause loops.

thats how it aids in loop prevention.