CIS 656, Dr Ott, Fall 2005, Network Description.

Network Description, Project B.
Maximum Team Size is 2.
Minimum Team Size is 1.
Recommended Team Size is 2.
Project due 11/12/2005.

This is a hypothetical private network inside NJIT, with a private
address space. It is connected to the rest of NJIT, and thus to the
whole Internet, through a NAT (Network Address Translation) router.

A drawing of the network will soon be available at Dr Ott's website.

There are 14 networks (numbered I, II, ... XIV). There are 12 routers 
(numbered 1, 2, ... , 12), plus the NAT router.

Netw	Address		MTU
I	10.1.1.0/24	  576
II	10.1.24.0/22	 4464
III	10.1.8.0/22	 4352
IV	10.1.32.0/20	 1500
V	10.1.16.0/20	17914
VI	10.1.48.0/20	65535
VII	10.2.8.0/22	 1500
VIII	10.2.0.0/20	65535
IX	10.2.16.0/20	65535
X	10.2.32.0/20	65535
XI	10.3.0.0/16	65535
XII	10.2.4.0/22	 1500
XIII	10.2.64.0/22	 4464
XIV	10.3.3.16/28	65535  /* this network has only two interfaces. */

Routers and Interfaces

R1:  A1 to I, A2 to II, A3 to III, A4 to IV, A5 to V, A6 to IV.
R2:  A7 to V, A8 to VII.
R3:  A9 to VI, A10 to VII.
R4:  A11 to V, A12 to VIII
R5:  A13 VIII, A14 to IX.
R6:  A15 to IX, A16 to X.
R7:  A17 to X, A18 to IV, A30 to XIII.
R8:  A19 to VI, A20 to XI.
R9:  A21 to XI, A22 to VII.
R10: A23 to III, A24 to XIII, A25 to XII.
R11: A26 to II, A27 to XII.
R12: A28 to XI, A29 to XIV.
NAT: A31 to XIV.

Adresses of Interfaces:

A1   10.1.1.1
A2   10.1.24.1
A3   10.1.8.1
A4   10.1.32.1
A5   10.1.16.1
A6   10.1.48.1
A7   10.1.16.128
A8   10.2.8.1
A9   10.1.48.128
A10  10.2.8.2
A11  10.1.16.64
A12  10.2.0.1
A13  10.2.0.128
A14  10.2.16.1
A15  10.2.16.128
A16  10.2.32.1
A17  10.2.32.128
A18  10.1.32.128
A19  10.1.48.128
A20  10.3.0.1
A21  10.3.0.128
A22  10.2.8.3
A23  10.1.8.128
A24  10.2.64.1
A25  10.2.4.1
A26  10.1.24.128
A27  10.2.4.2
A28  10.3.0.64
A29  10.3.3.17	(was corrected 11/23/2005)   
A30  10.2.64.128
A31  10.3.3.18	(was corrected 11/23/2005)

Routing is ``min-hop'' (that is the RIP Protocol we will soon see in
class).  In other words, unless SSR or LSR dictates otherwise, routers
forward packets on the route that leads to the destination in the
smallest number of hops.

There are some ties. For example, R1 to IX can follow 
R1, R4, R5, direct delivery, or
R1, R7, R6, direct delivery.
(Both count as 3 hops.)

Ties are broken as follows:

R1 to VII  uses R3.
R1 to IX   uses R4.
R1 to XII  uses R10.
R1 to XIII uses R10

Added 11/27/2005:
There also is a ty for the route from R12 to V.
If you read this in time: please use R12 to XI to R8 to VI to R1 to V.
That is what my program does.
(maximizes minimum MTU: that was my choice.)
``Therefore'' also traffic from R12 to VIII and IX goes via R8 and R1.
(``Therefore'' is not correct in the sentence above: Traffic from R12 to 
V, VIII, IX need not have the same next hop in R12. For example, if 
RIP is used, they can be different, depending on the order of updates 
after routers or networks have been down. With OSPF it is more 
complicated.) 

All routers R1 - R11 have forwarding tables as follows:

For any destination address in one of the networks I, ... , XIV 
they use the forwarding policy as above.
For any other destination address they have a default route to or
``towards'' R12.

R12 does not have a default route. (It is a bright router!).
For any destination address in one of the networks I, ... , XIV 
it uses the forwarding policy as above.
For other destination addresses inside 10.0.0.0/8 : Unless SSR or LSR 
or so dictate otherwise, it discards the packet and sends an ICMP 
packet ``destination network unknown''.
Packets with destination address outside 10.0.0.0/8 it forwards to the
NAT router.

You will write a program that:

(1) From the input interface (A1 - A31) determines what input
interface and what router the packet arrives on, and prints this
information.

(2) If that router is either R1 or R12, determines what happens to the 
packet and prints a description as in the examples.

Format of the input will be as in project A.

So, to prevent questions: If the input router is not R1 or R12, you only 
identify the router. Nothing more.
And if the input interface is not one of A1 - A31 you are allowed to make
a joke  :-)  .

Please check my network description:

Are there any inconsistencies?
Multiple interfaces with the same address?
Interfaces with an address not in the network it is supposed to be in?
(etc).

If you find a problem, please let me know. 

Warning: There are ``longest prefix'' issues. 
(This network was designed either by an incompetent designer or a by a 
teacher trying to be tricky.)