Data communications for engineers Book

	Preface
1	Introduction	1
1.1	Why do systems communicate?	1
1.2	How do systems communicate?	2
1.3	Information content of digital codes	4
1.4	Data communications	8
1.5	Standards	11
1.6	The standards organisations	12
1.7	An example of a standard	14
1.8	Layered communications	14
1.9	Summary	18
2	Physical Communications Channels	20
2.1	Types of channel	22
2.2	Direction of data flow	23
2.3	Characteristics of channels	24
2.4	Channel sharing or multiplexing	30
2.5	Physical media	32
2.6	Transmission modes	37
2.7	Summary	39
3	Baseband Digital Transmission	40
3.1	Pulse shaping	40
3.2	Line codes	41
3.3	Detection of digital signals in noise	49
3.3	Summary	52
4	Analog Data Transmission	53
4.1	Amplitude shift keying (ASK)	53
4.2	Frequency shift keying (FSK)	55
4.3	Phase shift keying (PSK)	56
4.4	Detection of analog signals in noise	58
4.5	Summary	60
5	Error Control and Data Compression Codes	61
5.1	Introduction	61
5.2	Block codes	63
5.3	Cyclic codes	68
5.4	Convolution codes	73
5.5	Codes for data compression	76
5.6	Summary	79
6	Physical Layer Standards	80
6.1	Telephone channels	80
6.2	Modem standards	83
6.3	Standards related to the use of modems	85
6.4	Modem interface standards	86
6.5	Common data communications protocols	90
6.6	The Integrated Services Digital Network	90
6.7	Summary	93
7	The Data Link Layer	95
7.1	Logical links	95
7.2	The functions of the data link layer	96
7.3	Link topology	97
7.4	Flow control	99
7.5	Error control	101
7.6	Character-oriented protocols	102
7.7	Bit-oriented protocols	104
7.8	Implementation of the link layer	108
7.9	Commercial link layer protocols	109
7.10	Summary	110
8	The Higher Layers of the Protocol Hierarchy	111
8.1	The network layer	111
8.2	The transport layer	119
8.3	The session layer	122
8.4	The presentation layer	123
8.5	The application layer	124
8.6	Summary	124
9	Local Area Networks	126
9.1	LAN topologies	126
9.2	Media access methods	132
9.3	Problems with LANS	135
9.4	Interconnecting local area networks	137
9.5	Fibre Distributed Data Interface	139
9.6	IEEE 802 standards	141
9.7	Summary	143
10	The Future of Data Communications	144
10.1	Optical fibre networks	144
10.2	Fast packet switching and frame relay	144
10.3	Making networking easier	145
10.4	Summary	147
	Glossary of Terms and Acronyms	147
	Bibliography	162
	List of Standards	164
	Index	169