Concepts and comparisons of DHCP and NAT

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The use of DHCP and NAT is common in network protocols. Do you have some control over the two protocols? Here we have a specific introduction to these two aspects. First let's look at what DHCP is, what NAT is, and then compare the two.

1. DHCP

DHCP is an abbreviation for Dynamic host Configuration Protocol, which is divided into two parts: one is server side and the other is client? All IP network settings data is centrally managed by the DHCP server and is responsible for processing the client's D HCP requirements, and the client uses the IP environment data assigned from the server?

It has a period of leased address. It's like I have a lot of addresses. Fake into what you need. I'll lend it to you for a few days. Within a certain period of time (referring to the lease term has arrived) you will give me the address. The DHCP server. He has an IP address pool. If a computer comes first. He fished from the pool of IP addresses. I'll lend it to you. You're done.

2. NAT

NAT is the abbreviation for network address translation (translation)? is NAT and IP spoofing exactly the same concept? A feature provided by the IPF NAT is that the local local area network (LAN) behind the firewall is shared with an ISP-provided IP address to access the Internet public network? NAT automatically converts each PC's LAN IP address on the intranet to the IP address of a public network when it leaves the firewall? In addition, when a packet returns, the reverse conversion is also performed? In the IP address space, there are special scopes reserved for use by the NAT intranet LAN IP address? According to RFC 1918, you can use the following IP ranges for intranet, which are not routed on the Internet public network:
Start IP 10.0.0.0-end IP 10.255.255.255
Start IP 172.16.0.0-end IP 172.31.255.255
Start IP 192.168.0.0-end IP 192.168.255.255

3. Compare

DHCP. He's just a dynamic IP assignment. There is no private conversion to a public address.

An example of an image:

NAT is used to translate your company's internal address into an address recognized by the Internet, so your company's internal computers can browse the Internet. Usually when you buy Internet connections from your ISP, your ISP will give you several public IP addresses, but your company has hundreds and thousands of computers.

At this point, you use NAT for address translation, assuming you set 73.12.36.81 to your company's Internet access address, and when your internal computer wants to access the Internet, NAT maps their internal address to a port on 73.12.36.81, for example : 73.12.36.81:9999, so that n multiple computers using the same public IP Internet access function? If you do not set up NAT, the intranet IP is not recognized in the public network, you can not access the Internet?

DHCP is used to dynamically assign IP addresses, Windows clients by default use DHCP to obtain the intranet IP address, after the establishment of DHCP they can automatically get IP address for network access, if not DHCP, computer, a set of one, it is a thing no one want to do? DHCP allows your internal clients to quickly get their IP addresses, and NAT allows these IPs to access the Internet.

Concepts and comparisons of DHCP and NAT