blocking

1. The intentional denying of access to a network, networked device such as a switch, router, circuit, or networked resource, such as a database. 2. In reference to a voice switch (see Figure B-2) or other device intentionally engineered to block some call attempts during the busiest hour of the day.This approach involves the concept of Grade of Service (GoS), which is the probability of blockage during the busy hour, expressed as a decimal fraction of the calls anticipated to be blocked. See also busy hour, GoS, and non-blocking. 3. A characteristic of a switch that is not able to handle simultaneous connections for all attached devices or all switch ports.

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• 1A2
• 1Base5 (1 Mbps; Baseband; 500 meters)
• 1B+D
• 1. Domain Name System. The naming convention that divides the Internet into logical domains identified in Internet Protocol version 4 (IPv4) as a 32-bit portion of the total address.The standard convention is user@organization.domain, where user is the name of the end user, organization is the name of the enterprise or other organization owning or sponsoring the address, and domain is the type of entity owning or sponsoring the address.The administration of the DNS is the responsibility of Internet Corporation for Assigned Names and Numbers (ICANN). See also domain, ICANN, Internet, and IPv4. 2.
• 1. In storage, irrelevant material, usually zero (0) bits, added to a data block in order to fill it to a minimum size, to force certain fields of control data or user data into certain positions or sizes, or to prevent the user data from duplicating a bit pattern that has a specific control meaning. See also block. 2.
• 1 cps, 1 Hz
• 1+ Dialing
• 1G (1st Generation)
• 1G (1st Generation)
• 1-persistent carrier sense multiple access (1-Persistent CSMA)
• 1-Persistent CSMA (1-Persistent Carrier Sense Multiple Access)
• 1+ WATS
• 1xEV-DO (one carrier EVolution-Data Optimized)
• 1xRTT (one times Radio Transmission Technology)
• 2
• 20
• 2:1
• 2:1
• 2:1
• 218–219 MHz Service
• 22
• 23B+D
• 23B+D
• 24
• 256-QAM