Category Archives: Labs

Hot Standby Router Protocol (HSRP) Part 2

HSRP Parameters We configured the HSRP on two routers and here is the status of both routers. R2 says it is Active router. R1 says it is Standby router and active router is the one that has IP address 192.168.0.3. Now we turn off the active router and see the status of this router. Now R1 says that it is active router and it is the only router running HSRP because it says that it does not know any standby router. HSRP Roles Read more […]

External Gateway Routing Protocol

Border Gateway Protocol (BGP) is an exterior routing protocol that connects two separate networks that are owned by two completely different authorities. This is the protocol that is used in the Internet. BGP always work with an IGP to route the traffic. BGP is not intelligent it does not calculates bandwidth and any other mechanism for traffic transmission, all it does is choose the route that has shortest path. We can refer path as its metric, it counts Read more […]

Hot Standby Routing Protocol (HSRP)

HSRP is the redundant gateway to the other network. It is Cisco proprietary. Suppose that you are working with the network architecture shown as above and you are sending traffic using a routing protocol, we do not know what path will the router choose to send the traffic because we do not know the underlying routing protocol. Now suppose that the Router B somehow fails to work then what will other routers do? The answer is the routing protocol will take care of it and will transmit Read more […]

Spanning Tree Protocol Part 2

Once again this is our architecture and in this lecture we will learn how to change the priority number to change the root bridge. This is lab design where we are working. Types of Roles In STP the ports are assigned to 3 roles. ·       Designated is the port which is allowed to forward traffic. ·       Root is the port closer to the root bridge and cannot be shut down. ·       Non-designated/Alternative is Read more […]

External Gateway Routing Protocol

Border Gateway Protocol (BGP) is an exterior routing protocol that connects two separate networks that are owned by two completely different authorities. This is the protocol that is used in the Internet. BGP always work with an IGP to route the traffic. BGP is not intelligent it does not calculates bandwidth and any other mechanism for traffic transmission, all it does is choose the route that has shortest path. We can refer path as its metric, it counts Read more […]

WAN Connectivity

WAN connectivity comes into the play when your organization has to connect to the Internet or the branch offices. It plays an important role in today’s era because without WAN connection there is almost no business, we have to have use Internet to do the taks. This is the simple diagram illustrating the WAN connectivity where you control the LAN and then Service Provider and Internet comes that you do not control. The router that gets us connected to the WAN is called Edge router. Read more […]

Generic Routing Encapsulation

GRE tunnels are used to hide the complexity of network. It works exactly like VPN tunnel and the only difference between GRE & VPN is encryption. As GRE does not do encryption, it sends data in plaintext. Question: The question is why do we bother to use this if it does not support encryption and work exactly like VPN? Answer: The answer is that we use this because it is easier and it does not requires complex configuration as VPN does. Read more […]

Point-to-Point Protocol Part 2

Multi-Link PPP It is another cool feature of PPP, which offers to combine multiple links and create an stronger link that could support more bandwidth, load balancing, and mitigation of single point of failure. This functionality is similar to Ether-channel. In multilink-interface we need to assign it IP and we take out IPs from serial interfaces, then we make a virtual interface and assign interfaces to that virtual link. This task is performed while you have at least two interfaces Read more […]

Spanning Tree Protocol

Spanning tree protocol is a mechanism to prevent loops among switches. There could be a loop in one switch as well, but we are here considering multiple switches and preventing them to create a loop. Loop is the condition where your switch sends a packet from one interface and somehow the same packets get back to same switch on difference interface.This is layer-2 switch and are comparatively dangerous than Layer-3 loops. This loop ends up in a broadcast storm. The simplest solution Read more […]

Point-to-Point Protocol (PPP)

Serial ports do not have MAC address. The question is how the serial connection works then if it does not have MAC address because at the end of the day we have to have layer-2 transimission. There are other technologies such as PPP, HDLC, Frame-Realy, and MPLS that work on layer-2 in serial connection. Frame-relay and MPLS are two protocols that isolate the data of multiple customers using a single line. PPP is the technology that ensures that you own the equipments and line, Read more […]