Data center cabling method summary (3)

WiringThe method is as follows:

Q: What is the future of CATV in the access network? Is there a trend to replace ADSL?

Answer: CATV generally uses the hybrid Connection Technology of copper fiber optic cables of HFCs. It supports transmission of cable TV signals, voice, data, and other information. It can also achieve the integration of business networks, but from the current national industry-related laws and policies: CATV network is mainly used for cable TV networks. ADSL is also a copper cable access technology, which can also achieve multi-service access. However, it is currently mainly used for voice and data services and is a broadband access method for telecom operators. All access technologies, such as the current use of EPON, can achieve business integration. Therefore, they can be achieved technically. Various technologies have their own characteristics and cannot fully describe who can replace.

Q: The term "short link resonance" is displayed during a course ". What is "short link resonance )?

A: This is a good question. It involves wiring design standards and product optimization.

The short link resonance you mentioned refers to the superposition of unbalanced or noisy signals in a short link (less than 15 meters, communication failure (signal reflection between the shorter links is easier to overlap ). We all know that the permanent link is less than 90 meters, but the standard also requires more than 15 meters, which can avoid the "short link" problem. That is to say, when the link between two distribution frames or modules is shorter than 15 meters, the link test will often fail. This phenomenon often occurs in cat5e and cat6 cable systems. We usually have a "short link" problem.

However, the problem is not so terrible. Some manufacturers have optimized their own products or implemented signal compensation technology, so that they can achieve the corresponding performance in the short chain. For example, it can be used at 7 meters or a shorter time. At the same time, the tester manufacturer is also testing the adapter for optimization to adapt to changes in cable products.

All you need to know is that the shorter the link, the better.

Q: Question 1: There are many ways to connect to a network, but I have not found a book that can be fully understood. Can you summarize it? From dial-up to optical fiber access and other access methods, provide a practical operation manual or solution with various access cases.

Question 2: leased line connection. Connect networks in different plots to form a LAN. Which methods are available? If I applied for an SDH/DDN/MSTP leased line access in China Telecom, can I use the SDH/DDN/MSTP of China Netcom to connect to each other in another region?

Answer: Question 1: There are a variety of ways to connect LAN to the computer's Internet. Currently, most users use the following methods:

Directly connect to China Telecom or other (such as technology and campus network) through a single-mode optical fiber cable from the egress optical port of the backbone Ethernet switch of the LAN (10 M/100 M/1000 M) after the carrier's optical fiber distribution frame, it can communicate with the WAN.

The egress port of the backbone Ethernet switch and the router that complies with the corresponding communication service network interface equipment should be considered to meet the needs of the egress transmission bandwidth. Currently, 2 M (E1) is generally used) is the Basic access method.

The ADSL, EPON, and wireless broadband access modes provided by telecom carriers are also based on the carrier's interface bandwidth requirements based on the egress bandwidth.

You can access the Internet through a user terminal device or a set-top box in a cable TV network.

The simplest is to use a telephone line and a modem to dial up the Internet.

Of course there are many access network technologies. The people's post and telecommunications Publishing House has a book devoted to the access network technology. In addition, the communication industry has released relevant specifications for the construction of access network systems. These are the technical documents that can be learned from them.

Question 2: If the network is switched over a leased line, SDH/MSTP/DDN/device of the same telecom operator should be used in general, however, it is also possible that a telecom operator will communicate with SDH of some private networks to provide users with remote services. You can negotiate with the carrier in a specific project.