IPv6 Stateless Autoconfiguration is a capability of a host to automatically acquire an IP address without needing DHCP. It uses its link-local address and the Neighbor Discovery Protocol (NDP) to do this. Each device creates a link-local address for itself based on the prefix FE80:: and the interface MAC address. This address is only valid […]
Eplain 5 EIGRP packets in sequence. Which packets are sent as multicast and which are sent as unicast? What is difference in the output of commands “show ip EIGRP topology” and “show ip EIGRP topology all-links”? What is criteria to become a Feasible Successor? Explain DUAL and RTP algorithms used by EIGRP. What is Stuck […]
In this article, we will discuss the similarities and differences between OSPF and ISIS Protocols. In this article we will compare OSPF and ISIS and discuss their similarities and some key differences between them. There are many similarities between the OSPF and ISIS. Below are few main similarities between both protocols. Both OSPF and ISIS […]
When we try to connect to a remote subnet/prefix from a router (for example, Ping, Telnet, or FTP), following basic routing rules are followed in given order. Select the route with longest mask (subnet mask). Select the route with best Administrative Distance. Select the route with best metric. If equal metric paths/routes exist, perform load […]
MPLS LDP IGP Sync is feature used to avoid traffic blackhole scenarios in the MPLS VPN networks. The traffic blackhole could occur when IGP is running up and fine on a Backbone link but, LDP is down. This could be due to mis-configuration or due some hardware/software bug issues in the network. To avoid such […]
We can change the metric learned by default (hop count) using the Offset-lists in RIP. In above topology, on router R1, we see the route for prefix 192.9.1.5/32 learned via 3 paths, i.e. via R2, R3, and R4 with equal metrics (hop count 2). Important Note: In RIP, Hop count or the Metric gets increased […]
OSPF behaves differently while peers are connected using various kind of networks. Below are the different Network Types: Point to Point Broadcast Non-Broadcast Multi Access (NBMA) Point to Multi-point Broadcast Point to Multipoint Non-Broadcast This article will discuss the details of OSPF Non-Broadcast Multi Access Network. In OSPF Non-Broadcast Multi Access Network, OSPF runs the […]
BGP LOCAL-AS CONCEPT – Command Syntax neighbor x.x.x.x local-as local-AS-numberneighbor peer-group local-as local-AS-number Local-AS cannot be customized for individual peers in a peer group. Local-AS cannot have the local BGP protocol AS number or the AS number of the remote peer. The local-as command is valid only if the peer is a true eBGP peer. […]
Encryption is a method that encodes the data that is unreadable by unintended parties. For example we want to send a text “The wardrobe key is on the kitchen shelf” secretly to another peer. This is clear text information and can be read by the hacker easily. With help of encryption we can encrypt this […]
Route Redistribution in EIGRP: Redistribution is a technique using which the boundary routers connecting different routing domains can exchange and advertise routing information. In this article, we will learn how to redistribute any routing protocol into EIGRP. Below syntax is followed. The command has to be configured in router configuration mode for the Route Redistribution […]
This blog helps you understanding and grasping IPv6 Header Details. IPv6 is the replacement Internet protocol for IPv4. It corrects some of the deficiencies of IPv4 and simplifies the way that addresses are configured and how they are handled by Internet hosts. IPv4 has proven to be robust, easily implemented, and interoperable, and has stood […]
HomeINTERVIEW QUESTIONSBGP INTERVIEW QUESTIONS Explain Split-Horizon, Synchronization rules. Which 2 new attributes are seen when we enable summarization in BGP? Why BGP specifically chooses neighbor method for creating sessions and why not the sessions are allowed to be configured dynamically as happen in IGPs(say EIGRP and OSPF). Two peers for […]
RIP does not have any way of reliability therefore the updates are sent periodically. RIP can also configured for generating triggered updates, however this is not discussed in this article. RIP uses 4 timers in order to manage the advertisement of updates. RIP Update Timer It is the time between each update interval. By default […]
Hot Standy Router Protocol or HSRP is similar to Virtual Router Redundancy Protocol (VRRP) or Gateway Load Balancing Protocol (GLBP) and is used to build a virtual gateway for LAN hosts for redundancy purpose. Before discussing How HSRP works and what are its features, it is important to understand the need of gateway redundancy. R1#sh […]