Canon imageRUNNER 2545i, Руководство по настройке системы

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Glossary 9-19
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S NTP
Simple Network Time Protocol. A simplified version of NTP. This protocol enables
computers in a network to synchronize their system times with a public time server
used around the world. The time public NTP servers provide is generally accurate to
within milliseconds.
S pool
Simultaneous Peripheral Operations On-Line. “Spooling” means putting jobs in a
buffer, which is a special area in memory or on a disk. Devices access data at
different rates. The buffer provides a holding area where the data is held until the
device for which it is meant is ready to access it.
SS L
Secure Sockets Layer. A protocol that ensures security and privacy when transmitting
private documents over the Internet.
SS L encryption
SSL uses two keys to encrypt data: a public key, which is known to “everyone,” and a
private or secret key, which is known only to the recipient of the message.
S tartup time
If the machine is connected to a switching hub, it may not be able to connect to a
network when it is powering ON. This occurs because the spanning tree process,
performed between switching hubs, prevents them from communicating with each
other immediately after the machine connects to the network. A delay in the startup
time is necessary for the machine to connect to the network properly.
S ubnet
A portion of a network, which may be a physically independent network segment, that
shares a network address with other portions of the network, and is distinguished by
a subnet number. For example, all devices with IP addresses that start with
100.100.100. would be part of the same subnet.
S ubnet Ma s k
The method used to determine to which subgroup, or subnet, an IP address belongs.
On TCP/IP networks, all devices whose IP addresses have the same prefix would
belong to the same subnet. Dividing a network into subnets is useful for both security
and performance reasons.
S witchin g hub
A network connection box to which a number of computers can be connected.
Conventional hubs send each data packet to every connected computer on the
network, whereas a switching hub forwards data packets from the network to the
appropriate computer, according to the packet’s address. Since a switching hub
forwards packets only to their intended recipients, it provides greater efficiency.