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The oldest lan technology is?
ARCnet
What is ARCnet?
ARCNET (also CamelCased as ARCnet, an acronym from Attached Resource Computer NETwork) is a local area network (LAN) protocol, similar in purpose to Ethernet or Token Ring. ARCNET was the first widely available networking system for microcomputers and became popular in the 1980s for office automation tasks. It has since gained a following in the embedded systems market, where certain features of the protocol are especially useful. Original ARCNET used RG-62/U coax cable of 93Ω impedance and either passive or active hubs in a star-wired bus topology, a layout eventually copied by modern twisted pair Ethernet LANs. At the time of its greatest popularity ARCNET enjoyed two major advantages over Ethernet. One was the star-wired bus; this was much easier to build and expand (and was more readily maintainable) than the clumsy linear bus Ethernet of the time. Another was cable distance - ARCNET coax cable runs could extend 2000 feet (610 m) between active hubs or between an active hub and an end node, while the RG-58 (50Ω) 'thin' Ethernet most widely used at that time was limited to a maximum run of 600 feet (183 m) from end to end. Of course, ARCNET required either an active or passive hub between nodes if there were more than two nodes in the network, while thin Ethernet allowed nodes to be spaced anywhere along the linear coax cable, but the ARCNET passive hubs were very inexpensive. Passive hubs limited the distance between node and active hub to 100 feet (30 m). More importantly, the "interconnected stars" cabling topology made it easy to add and remove nodes without taking the whole network down, and much easier to diagnose and isolate failures within a complex LAN. To mediate access to the bus, ARCNET uses a token passing scheme, a bit different from that used by Token Ring. When peers are inactive, a single "token" message is passed around the network from machine to machine, and no peer is allowed to use the bus unless it has the token. If a particular peer wishes to send a message, it waits to receive the token, sends its message, and then passes the token on to the next station. Because ARCNET is implemented as a distributed star, the token cannot be passed machine to machine around a ring. Instead, each node is assigned an 8 bit address (usually via DIP switches), and when a new node joins the network a "reconfig" occurs, wherein each node learns the address of the node immediately above it. The token is then passed directly from one node to the next. Historically, each approach had its advantages: ARCNET added a small delay on an inactive network as a sending station waited to receive the token, but Ethernet's performance degraded drastically if too many peers attempted to broadcast at the same time, due to the time required for the slower processors of the day to process and recover from collisions. ARCNET had slightly lower best-case performance (viewed by a single stream), but was much more predictable. ARCNET also has the advantage that it achieved its best aggregate performance under the highest loading, approaching asymptotically its maximum throughput. While the best case performance was less than Ethernet, the general case was equivalent and the worst case was dramatically better. An Ethernet network could collapse when too busy due to excessive collisions. An ARCNET would keep on going at normal (or even better) throughput. Throughput on a multi-node collision-based Ethernet was limited to between 40% and 60% of bandwidth usage (depending on source). Although 2.5 Mbit/s ARCNET could at one time outperform a 10 Mbit/s Ethernet in a busy office on slow processors, ARCNET ultimately gave way to Ethernet as improved processor speeds reduced the impact of collisions on overall throughput, and Ethernet costs dropped. In the early 1980s ARCNET was much cheaper than Ethernet, in particular for PCs. For example in 1985 SMC sold ARCNET cards for around $300 whilst an Ungermann-Bass Ethernet card plus transceiver could cost $500. Another significant difference is that ARCNET provides the sender with a concrete acknowledgment (or not) of successful delivery at the receiving end before the token passes on to the next node, permitting much faster fault recovery within the higher level protocols (rather than having to wait for a timeout on the expected replies). ARCnet also doesn't waste network time transmitting to a node not ready to receive the message, since an initial inquiry (done at hardware level) establishes that the recipient is able and ready to receive the larger message before it is sent across the bus. One further advantage that ARCNET enjoyed over collision-based Ethernet is that it guarantees equitable access to the bus by everyone on the network. Although it might take a short time to get the token depending on the number of nodes and the size of the messages currently being sent about, you will always receive it within a predictable maximum time; thus it is deterministic. This made ARCNET an ideal real-time networking system, which explains its use in the embedded systems and process control markets. Token Ring has similar qualities, but is much more expensive to implement than ARCNET. In spite of ARCNET's deterministic operation and historic suitability for real-time environments such as process control, the general availability of switched gigabit Ethernet and Quality of service capabilities in Ethernet switches has all but eliminated ARCNET today. At first the system was deployed using RG-62/U coax cable (commonly used in IBM mainframe environments to connect 3270 terminals and controllers), but later added support for twisted-pair and fibre media. At ARCNET's lower speeds (2.5 Mbit/s), Cat-3 cable is good enough to run ARCNET. Some ARCNET twisted-pair products supported cable runs over 2000' on standard CAT-3 cable, far beyond anything Ethernet could do on any kind of copper cable. (Indeed, ARCNET has been demonstrated running successfully across coat hanger wire!)[citation needed] In the early 90s, Thomas-Conrad Corporation developed a 100 Mbit/s topology called TCNS based on the ARCNET protocol, which also supported RG-62, twisted-pair, and fiber optic media. TCNS enjoyed some success until the availability of lower-cost 100 Mbit/s Ethernet put an end to the general deployment of ARCNET.
Does wifi reveal your ip address?
Just as much as Ethernet or Arcnet does: you simply cannot use TCP/IP (and UDP/IP), without revealing your IP address.
What are the types of topologies networking?
Bus star ring mesh hybrid
In what year was the Ethernet Computer Network established?
The answer to this depends upon how you define "computer network". If you are referring to the Internet, you can see the history at: http://www.davesite.com/webstation/net-history.shtml If you are referring to local area networks (LANs), I'd like to make a case for ARCnet, which was introduced commercially by Datapoint in 1977, though we used it internally before that. ARCnet used a token-ring architecture, supported data rates of 2.5 Mbps in its initial form, and connected up to 255 computers. One advantage of ARCnet was that it permitted various types of transmission media -- twisted-pair wire, coaxial cable, and fiber optic cable -- to be mixed on the same network. If I recall correctly, we had something like 6,000 ARC networks installed in customer sites when the first Ethernet was sold to a customer. ARC, by the way, stands for "Attached Resource Computer". You can read more about ARCnet at: http://www.old-computers.com/history/detail.asp?n=23&t=3 but the diagram is wrong. It shows computers connecting directly to other computers, rather than all of them being connected to hubs as ARC requires. ARCnet is still alive, though no longer used in its original capacity as a data processing and office automation tool. See: http://www.arcnet.com/abtarc.htm
How do you write 'works' in French?
"works" as in "(road)works" is "travaux" (masc.) "works" as in "she works" (the verb) is "travaille".
When was Early Works for Me If It Works for You created?
Early Works for Me If It Works for You was created in 1998.
It works!?
It works!
When was Early Works for Me If It Works for You II created?
Early Works for Me If It Works for You II was created in 2009.
How do you spell works in Spanish?
Works, as in "he works," would be "trabaja."
How does www.alibaba.com works?
works?
Does plexus slim works?
It works for me!
