All questions base on CCNA routing and swtiching essentials Chapter 1 1. When a packet is sent over a path which involves multiple hops, when do the source and destination IP addresses change? If each...

Chapter 1
1. When a packet is sent over a path which involves multiple hops, when do the source and destination IP addresses change? If each hop is using an Ethernet channel, when do the source and destination MAC addresses change?
In the routing process the sources address and destination address do not changes however MAC source and destination address varies at each segment. The changes happen on Layer 2 for each segment.
2. What does a router do when a packet a
ives on an interface?
It is a control plane performed by the Routers. Routers has a routing table where to route, what to route. It gets information using static or dynamic configuration, called routing protocol (OSPF, EIGRP, RIP etc.) it has to discard layer 2 header information on the a
ival of packet (the mac address). Then find for L3 layer 3 information, the source and destination address.
For moving layer 3 packet, it searches for longest-prefix match in IP table for destination address. And then mask to get known about the best route or path to forwarding the packet.
3. If a router has a choice between two routes to a destination, one which has been provided by the routing protocol OSPF and the other by the routing protocol RIP, which one will the router choose? Why?
If a router has a choice between routes to a destination, then based on the network having hop count would make decide which routing protocol has to be chosen. Whether it would be OSPF or RIP routing protocol. Below description gives the idea that how router choice routing protocol and why:
1. If network hop count is exceeded, then 15 in any route the RIP would not work as its infinity defined as 16. It is effective and good for small network while OSPF would be chosen if there is large dynamic networks presents.
2. If bandwidth is the concern, then OSPF would be the chosen one by the router because RIP send entire table router to router in every 30 Second. On the other hand, OSPF share link state information in every 30 minutes.
3. In large network RIP shows slow convergence, unlike OSPF which is faster then RIP.
So based on entire information above the route chooses routing protocol.
4. What is load balancing?
Load balancing is used to improve and optimize the use of resources across multiple computing domains. It distributes the workloads to ensure the minimum response time, overload avoidance and having maximum throughput. It also has concern with reliability and availability of responses by using multiple components instead of single component.
5. How can a router learn about routes?
Forwarding IP packets one to another network is the working of router and connected with two NIC cards to connect to network or devices. They have configurations to find appropriate path, the fastest on using different algorithms implemented which are called routing algorithms. It’s also has metric values based on preference...