Telecom Voice Gateways

It is the process of temporarily storing the data so that

the data is available for some activity (re-sequencing etc.)

The result of this is delay in delivery of the packets and

hence, variation in speed of packet delivery.

In Band (Single Frequency, Multi-Frequency (MF), and Dual-Tone Multi-Frequency (DTMF)), Common Channel Signalling (CCS) and Signalling System 7 (SS7) is used Between the exchanges.

But CCS and SS7 are more cheaper than MF.

+48 voltsb) -48 voltsc)

non maskable interrupt r those 2 whom processor must have 2 respond instantly.....

4 maskable interrupts it should complete current instruction n then come over it..

Program Counter in a microprocessor (or CPU) is a pointer

instruction of the program to tell where the CPU to look

for the next instruction.

if you sample a signal in regular

intervals of at least twice the highest channel frequency,

the sample will contain enough information to accurately

reconstruct the signal.

Human Audible Range: 20 – 20,000 Hz

Human Speech: 200 – 9000 Hz

Telephone channel: 300 – 3,400 Hz

Nyquist theorem: 300 – 4000 Hz

Sample size = (2 * 4000) 8000, 8000 * 8 bits =

64,000 bps = 64 kbps

256

SINCE, 1 BYTE=8 BITS

THE LOGIC IS 2^8=256(2 TO THE POWER OF 8)

Logically speaking, whatever be the number of hops, the

fixed delay should not go more than 150ms (one-way).

The satellite delay for single hop SCPC link is about

525-550ms. But for TDMA network, the delay varies

between 550ms - 700ms.