Thanghadurai

MPLS is considered as 2.5 Layer protocol due to its special feature of LDP protocol. LDP stands for Label Distribution protocol. If the network is built up with MPLS network. Let us assume that A network is in some ABC location and Z network is in some XYZ location. Also, these A and Z networks are 10 to 20 hosp away from each other with redundant paths. When the initial packet from either A to Z or vice versa it will be using HARDWARE BASED PACKET FORWARDING using IP Routing table. After this, each route in the MPLS network will be logically linked with some kind of labels which understand by all MPLS routers. So after the 1st successful conversation between A to Z network or vice versa, the data/packet transfer will be based on Labels. So Routers doesn't want to look at the L3/Routing/Forwarding table every time for the packet forwarding. This increases the Router's performance and reduces the memory consumption with fast packet transmission. MPLS is seeking the help of IP routing table initially for the Label distribution for the respective routes and then after the Labels are just like the Layer 2 address. So MPLS is operating with the help of both Layer 2 as well as Layer 3, so this is why MPLS is called as Layer 2.5 protocol.

To manage a small computer LAN you can do so many things but I listed out few things below which gives some idea how to form a LAN network and to manage with basic security: - To form a small LAN network you need to buy a device called hub/bridge/switch which available in the market as per your budget. - If you go for Hub you may experience a collision in your network. - So either you can go for Bridge or Switch from any vendor like TP-Link, D-Link, Cisco,... - Once you get the device[Bridge/Switch] you need to connect your end devices like PC, Laptop, Printer, etc with the Bridge/Switch using Straight-through ethernet cables. - Assign the IP address to all the end device in the format of Same Network Address and different Host Address. - If it is Cisco Switch, you can shut down the unused ports for security reasons. You can enable BPDU filters, Sticky MAC Address and so many things to secure your network at First Level itself. - If it is any other vendors, check on the Internet what kind of security features does it supports.

Let me give a scenario:: You are a Network Administrator working in some NOC environment and you are receiving a call from one of your client saying that connectivity is down. So you will be asking the client "What is their Site IP address??" This means, actually which Network network they belong to. Example: If classful 192.168.0.0/24 , 172.16.0.0/16 OR If it is classless 192.168.0.0/26, 172.16.0.0/22 With this information, you can get the client details if it is stored in your company database and further you can start troubleshooting the issue.