CMIT 350 Name(s):___________________________________________________ Edit this file and BOLD your answers. Using JimSim Comment out all the interface and routing configuration in the .cfg files. We want the routers to start up with no IP configuration. As you go thru this exercise, write down the IP addresses of the interfaces: Router1 Router2 Router3 e1 e0 e0 e1 e1 e0 | | | | | | ---- ---------------- --------------- ------ Our scenario: we've been assigned one class C network number but we have four networks. So we will subnet the class C network. None of the subnets will need more than 14 hosts and we want to be as frugal as possible with our alloted class C network, so we will make our subnets as small as possible. We'll use the class C private network of 192.168.0.0 instead of some class C registered network for this lab exercise. We'll subnet the class C 192.168.0.0/24 into subnets using a /28 prefix which is mask 255.255.255.240. Each subnet thus has four bits in the host part, giving 16 possible addresses of which two are reserved for the network and broadcast addresses. Since four bits have been "borrowed" from the host portion to be the subnet bits, 16 subnets are possible of which two are discouraged from being used, viz. the zero-subnet (subnet bits all 0's) and the broadcast-subnet (subnet bits all 1's). This subnetting doesn't use all the address space (only four of the 16 possible subnets will be used), leaving other subnets for other, unseen parts of our internetwork. Note that here the zero subnet 192.168.0.0/28 will not be used, as per CCNA "recomendation". Note that each interface here will have either the first or last usable host address in its subnet. Configure the Ethernet between R1 and R2: network: 192.168.0.16/28 R1's E0 192.168.0.17 R2's E0 192.168.0.30 A route to what network is in R1's routing table:______________________ Can R1 ping R2:____ Use 'show ip interface' to see what the broadcast address of R1's E0 network is: _________________________ Configure the Ethernet between R2 and R3: network: 192.168.0.32/28 R2's E1 192.168.0.33 R3's E1 192.168.0.46 Routes to what networks are in R2's routing table: __________________________ What is the broadcast address of R2's E1 network:_____________ Can R2 ping R3: _____ Can R3 ping R2: _____ Can R2 ping R1: _____ Can R1 ping R2's E1: _____ What is the error message:______________ Can R1 ping R3's E1: _____ What is the error message:______________ Can R3 ping R2's E0: _____ What is the error message:______________ Can R3 ping R1's E0: _____ What is the error message:______________ Moral of this exercise: subnets are as much individual separate networks as classful networks. There are two separate networks here now: 192.168.0.16 and 192.168.0.32 (each with a 28 bit prefix, or subnet mask of 255.255.255.240). There is no 192.168.0.0 network here. Add a static route in R1 to the 192.168.0.32 subnet getting there via R2's E0 interface as the next-hop address. What entry has been added to R1's routing table: ________________ Add a static route in R3 to the 192.168.0.16 subnet getting there via R2's E1 interface as the next-hop address. What entry has been added to R3's routing table: ________________ Now can R1 ping R2's E1: _____ Now can R1 ping R3's E1: _____ Now can R3 ping R2's E0: _____ Now can R3 ping R1's E0: _____ The "next" contiguous subnet of the same size is 192.168.0.48/28 Assign R1's E1 to be the lowest numbered host in that network. What is that:_______________ What new entry is in R1's routing table:_________________________ What is the broadcast address of this network:_____________ The "next" contiguous subnet of the same size is 192.168.0.64/28 Assign R3's E0 to be the highest numbered host in that network. What is that:_______________ What new entry is in R3's routing table:_________________________ What is the broadcast address of this network:_____________ Can R1 ping R3's E0: _____ What is the error message:______________ What three networks does R1 have routes to:_______________________ Add a static route in R1 to the 192.168.0.64 subnet getting there via R2's E0 interface as the next-hop address. What entry has been added to R1's routing table:_____________________ Now can R1 ping R3's E0: _____ Why not:_________________________ That's right, R2 needs to know where to forward the packets. Because it doesn't know about the 192.168.0.64 network it drops packets destined to it. Add a static route in R2 to the 192.168.0.64 subnet getting there via R3's E1 interface as the next-hop address. What entry has been added to R2's routing table: ________________ Now can R1 ping R3's E0: _____ Now can R3 ping R1's E1: _____ What is the error message:______________ Add a static route in R3 to the 192.168.0.48 subnet getting there via R2's E1 interface as the next-hop address. What entry has been added to R3's routing table: _____________________ Now can R3 ping R1's E1: _____ The packets are being dropped at R2 because it doesn't know about the 192.168.0.48 network. So: Add a static route in R2 to the 192.168.0.48 subnet getting there via R1's E0 interface as the next-hop address. What entry has been added to R2's routing table: ________________ Now can R3 ping R1's E1: _____ Paste the entries of the routing tables of the three routers. Router 1: Router 2: Router 3: