For students who have studied the TCP / IP protocol, this is not a problem, the IP protocol. For the public, more explanation is needed.
IP in the IP protocol is an abbreviated form of two words: Internet Protocol, which translates to "IP protocol" in Chinese. The next question is, why is the IP protocol able to connect networks of all sizes in the world?
Looking at the word "Internet", it actually consists of two words: "Inter" and "net". "Inter" is translated into Chinese as "between, mutual", and "net" means "net" in Chinese, which can be translated into "interconnection between nets" when combined. The meaning is clear. The core goal of IP is to connect different networks. The network here can be a network with the same physical medium, or a network with different physical media, such as Ethernet, wireless network, ATM network, EPON / GPON, T1 / T3. The encapsulation format of the physical link layer of these networks is not the same, but the IP protocol has a natural ability to control them!
What's so special about the IP protocol?
The IP protocol has a highly abstracted capability. In the eyes of IP, all physical networks are a civilian serving themselves. Regardless of whether this network was once a relative of the imperial family (network layer, equivalent to IP status) or this network was once a nomadic trafficker (link layer, without routing capabilities), it is now a subject of the new IP king.
IP abstracts all networks into data link layers. In the eyes of IP, the only difference between these data link layers is the difference in the encapsulation format. This is easy. An Ethernet data packet is received by the router's Ethernet Incoming Interface. As long as the data link layer encapsulation is peeled off, only IP packets are left.
IP looks up the routing table and finds the outgoing interface. The outgoing interface is T3 and the encapsulation type is HDLC. Then the router only needs to add the layer 2 HDLC encapsulation information to the header of the IP packet, and then this brand-new data can be added. The packet was sent out.
What to do if the data packet reaches the end of the T3 line? If you understand the explanation above, it is easy to understand this, this is just a mechanical iterative process!
Can you design a new Internet Protocol instead of the IP protocol?
The feeling of being a king is certainly good, but the IP protocol becoming the king of the Internet means difficult to measure conquest. Defeated each opponent and continued to expand their territory. Once the trend is formed, it will be unstoppable. Network devices and hosts support TCP / IP. If your device does not support it, you will not be able to interconnect with other networks. Who will not support it?
This is like the trend of two-dimensional codes for mobile payments. Merchants say that we do n’t support it. Is n’t that a problem with money? Why can QR codes form the trend of mobile payments? Of course, because of its convenience, if it is not easy to use, it is difficult to form a trend.
IP, put the customer's package in the trunk, and take the user's heavy load on the road:
o Country road (a type of network) for a while
o Ferry across the river after a while (a network type)
o Take the highway after a while (a type of network)
o After a while at the beach, I got on a cargo plane (a network type)
o Get off the plane and drive on the highway (a network type)
o Get off the highway and drive down American country roads (a type of network)
o Finally arrive at the door of a small villa, the IP will send the package to the villa owner
Q1: Are there any duplicate network types?
Yes, there are not many types of networks on the Internet that can survive the fittest!
Q2: Why can IP deliver the package to its destination?
The IP address has the address of the receiver. The address of the receiver does not change each time the network type is changed.
The above is the news sharing from the PASSHOT. I hope it can be inspired you. If you think today' s content is not too bad, you are welcome to share it with other friends. There are more latest Linux dumps, CCNA 200-301 dumps and CCNP Written dumps waiting for you.
Comments