TOPIC: ios default routes; CCNA related question

hi all.
ccna-curriculum states that

Default routing begins with the administrator. Before routers can dynamically exchange information, an administrator must configure at least one router with a default route.

do they refer to the term dynamically by means of a default route? to my understanding it's completely possible to route packets and exchange routing tables even if no default route is configured, but the above sounds states otherwise. am i wrong?

I agree with you alpha. You do not need to assign a route for routers to exchange information.

As long as there is a valid communicatio path - ie IP address in the same network & subnet mask at either end of a connection and tehy can talk (ping etc) then they can start passing routing information eg RIP tables OSPF etc.

I think the confusion here is the term "dynamically exchange information", because it does not make it clear if they are taking about 'routing information' or pure 'data information' e.g a user sending an email.

Reading furthermore... 'administrator must configure at least one router with a default route'. This then makes everything clear. We know that if you want your router to exchange routing tables dynamically, that is, with the use of a routing protocol, you must enable the routing protocol process (e.g #router rip - to enable the Rip routing protocol). Since it mentions as a minimum configuration ' at least one default route' then it's clear that it is talking about the exchange of real user data e.g web, email e.t.c.

So, taking in consideration all the above, the statement is correct as you do need at least one default route in your router's routing table for it to send/receive data to and from networks beyond your local LAN.

If anyone has other suggestions, we would like to hear them.

cheers,

well, thanks alot gl0bal and chris.
things have become a bit clearer now. some phrases in there are a bit confusing sometimes.

greets

Chris,

Im trying to get a jist of your explanation here so I'm going to try and reword what you said and maybe tell me I'm right or way off. To configure a dynamic routing protocol such as RIP or OSPF, it does NOT need a default entry in the table. But when it comes to actually passing packets to and from interfaces USING the dynamic routing protocol in question, you need a default route in the table. Would this default route be the next adjacent router?

Almost got it.

Let me repeat what you just typed and make some changes to help you understand it:

[code:1]To configure a dynamic routing protocol such as RIP or OSPF, it does NOT need a default entry in the table. [/code:1]

Correct - to configure a dynamic routing protocol you simply need to enable it with the appropriate commands.

[code:1]But when it comes to actually passing packets to and from interfaces USING the dynamic routing protocol in question, you need a default route in the table. Would this default route be the next adjacent router?[/code:1]

We must define 'passing packets' here.

If 'passing packets' means user data (www, email ....), then you do need a default route which will be the next adjacent router or next 'hop'.

If 'passing packets' means routing protocol data (routing tables), then a default route will do you no good. Remember that when routing protocols are enabled on a router, they will automatically learn about their neighbors, without the need of any default routes.

Hope that helps.