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 Guide Resources FAQs Y2K White Paper Glossary |
Router Cable FAQs
- What should be considered when buying router cabling?
- What's the best choice?
- What are some common interfaces for serial data?
What should be considered when buying router cabling?
When purchasing wide-area equipment such as router and it's cabling, keep in mind that wide-area networking span many different devices and services. Purchasing considerations will vary depending upon the type of service and the kinds and amount of traffic that will be sent over it.
What's the best choice?
In general, which device you choose depends on your applications and the complexity of your network. Bridges connect the same network (as designated by the network number); routers connect different networks. If you want to connect two networks and they have the same network number, use a bridge. If the number is different, use a router.
Router
- What type of router is it (single- or multiprotocol, LAN, WAN, bridging, etc.)?
- What types of networks can be connected?
- How many ports are available?
- What protocols are supported?
- What LAN and WAN interfaces are supported?
- Does it provide bridging capabilities?
- What are the transmission speeds?
- What types of network monitoring and management capabilities are provided?
- Is it local or remote? Internal or external?
- What media and architecture are supported for the local network?
- What interfaces are supported for a remote link?
- How many ports are available?
- What are the local and remote transmission speeds?
- What type of network performance data can be collected?
What are some common interfaces for serial data?
Serial data transmission is the common method of sending data from one DTE to another. During a transmission, the data passes through a serial interface to exit a computer as serial data. These are some common interfaces for serial data:
RS-232 - Encompasses three types of connections electrical, functional, and mechanical. The RS-232 interface is good for the data-transmission range of 0–20 kbps/50 ft. (15.2 m). It utilizes unbalanced signaling and is generally used with DB25 connectors to interconnect DTEs (computers, controllers, etc.) and DCEs (modems, converters, etc.). Serial data exits through an RS-232 port via the Transmit Data (TD) lead and arrives at the destination device’s RS-232 port through its Receive Data (RD) lead. RS-232 is compatible with these standards: ITU V.24, V.28; ISO IS2110.
RS-449 - Is for functional/mechanical interfaces such as DTEs/DCEs that employ serial binary data interchange and are usually used with synchronous transmissions. It identifies signals (TD, RD, etc.) that correspond with the pin numbers for a balanced interface on DB37 and DB9 connectors. RS-449 was originally intended to replace RS-232, but RS-232 and RS-449 are not compatible in mechanical and electrical specifications.
RS-530 - Is the replacement for RS-449 and which complements RS-232. It is based on a 25-pin connection, which works with either electrical interface RS-422 (balanced electrical circuits) or RS-423 (unbalanced electrical circuits). RS-530 defines the mechanical/electrical interfaces between DTEs and DCEs that transmit serial binary data, sync or async, at rates from 20 kbps to 2 Mbps. (Maximum distance depends on the electrical interface.) RS-530 takes advantage of higher data rates with the same mechanical connector used for RS-232. Though RS-530 and RS-232 are not compatible, RS-530 is compatible with these standards: ITU V.10, V.11, X.26; MIL-188/114; RS-449.
RS-422 - Is a balanced interface with no accompanying physical connector. Manufacturers who use this standard alternate between many different connectors, including screw terminals, DB9, DB25 with nonstandard pinning, DB25 following RS-530, and DB37 following RS-449. RS-422 is commonly used in point-to-point communications conducted with a dual-state driver.
RS-485 - RS-485 copies or replicates RS-422. It may be used in multipoint applications where one computer controls many different devices. With RS-485 it can be interconnected to 64 devices.
V.35 - Is the international standard termed ''Data Transmission at 48 kbps Using 60-108 KHz Group-Band Circuits.'' It is typically used for DTEs or DCEs that interface to a high-speed digital carrier such as AT&T® Dataphone® Digital Service (DDS).
