Voic 802 11e over phần 2 pps
Voic 802.11e over phần 2 pps
... stops and
then enters into a random back-off procedure (Figure 2. 3). This prevents
18 Voice over 8 02. 11
16 Voice over 8 02. 11
Table 2. 2 (continued)
Mac Service Description
Station
Type
Disassociation ... tak
-
ing a structured view of the 8 02. 11 parameters. The formal specification of the
8 02. 11 MIB is Annex D of the 8 02. 11 specification. The 8 02. 11 MIB was
desi...
Voic 802.11e over phần 9 ppsx
... 97 2. 3900 2. 4500
Part 15 2. 4000 2. 4830
Fusion lighting 2. 4000 2. 4835
Part 18 2. 4000 2. 5000
Part 80 2. 4000 9.6000
ISM 8 02. 11b 2. 4010 2. 4730
Part 74 2. 4500 2. 4835
Part 101 2. 4500 2. 5000
Part 90 2. 4500 ... throughout the
building to ensure optimal coverage.
Economics of Vo8 02. 11 Networks 22 1
14
Economics of Vo8 02. 11 Networks
Why deploy a Vo8 02. 11 networ...
Voic 802.11e over phần 1 docx
... access
12 Voice over 8 02. 11
Interoffice Telephony 22 8
Enterprise Conclusion 22 8
Lower Barrier to Entry 22 9
Considerations in Bypassing the PSTN with Vo8 02. 11 22 9
Conclusion 23 0
References 23 1
15 ... VoIP 21 4
Conclusion 21 5
References 21 6
14 Economics of Vo8 02. 11 Networks 21 7
Vo8 02. 11 Works: Case Studies 21 7
Medical 21 7
Education 21 9
Financial Services...
Voic 802.11e over phần 3 docx
... 4 .2
ITU Voice Codecs and Their Performance
Standard
Data Rate
(Kbps)
Delay
(ms) MOS Codec
G.711 64 0. 125 4.8 Waveform
G. 721
G. 723
G. 726
16, 24 , 32, 40 0. 125 4 .2
G. 728 16 2. 5 4 .2
G. 729 8 10 4 .2
G. 723 .1 ... Camarillo, G., SIP Demystified, New York: McGraw-Hill, 20 02.
[7] Collins, D., Carrier Grade Voice over IP, 2nd ed., New York: McGraw-Hill, 20 02.
Voice over...
Voic 802.11e over phần 4 pdf
... power, the range of 8 02. 11 is extended to
tens of miles [1].
78 Voice over 8 02. 11
VoIP media
g
atewa
y
PSTN
IP network
Softswitch
8 02. 11a/b/g
Vo8 02. 11
PDA
Vo8 02. 11
phone
Vo8 02. 11
laptop
Wireless ... connection between a local telephone switch and a subscriber. WLL
88 Voice over 8 02. 11
WLAN 8 02. 11b
WWAN 8 02. 11a
WMAN 8 02. 16
Figure 6.3 Covering a metropolita...
Voic 802.11e over phần 5 docx
... performance and
120 Voice over 8 02. 11
1 12 Voice over 8 02. 11
Access point
Vo8 02. 11
p
hones
❘❙❚
❘❙❚
❘❙❚
❘❙❚
❘❙❚
❘❙❚
❘❙❚
❘❙❚
Internet
Router
IP phones
IP-PBX DMZ
server
Firewall
Hub
Figure 7. 12 Wireless ... starts at 0 again.
1 02 Voice over 8 02. 11
8 02. 11 access pointVo8 02. 11 phone
❘❙❚
❘❙❚
❘❙❚
❘❙❚
❘❙❚
❘❙❚
❘❙❚
❘❙❚
Intr
ude
r
Figure 7 .2 Interception in a network....
Voic 802.11e over phần 6 ppt
... Vo8 02. 11 Wireless Networks 133
Table 8 .2
The 11 Overlapping 8 02. 11b Channels
Channel Frequency (GHz)
1 2. 4 12
2 2. 417
3 2. 422
4 2. 427
5 2. 4 32
6 2. 437
7 2. 4 42
8 2. 447
9 2. 4 52
10 2. 457
11 2. 4 62
Source:
[2] .
is ... work with all possible 8 02. 11 physical layers
(original 8 02. 11, 8 02. 11, 8 02. 11a, and 8 02. 11g). The following sections
de...
Voic 802.11e over phần 7 doc
... and middle 8 02. 11a bands and 20 MHz for the upper U-NII band
(Figure 10.5).
176 Voice over 8 02. 11
8 02. 11 phone
2. 700 GHz
2. 400 GHz
2. 500 GHz
2. 600 GHz
Access
p
oint
Figure 10.3 The 2. 4-GHz band ... best
Engineering Vo8 02. 11 Networks for Maximum QoS 161
Which 8 02. 11 Protocols Are Best for Which Vo8 02. 11 Applications?
Four primary standards-based protocols are c...
Voic 802.11e over phần 8 pdf
... dBm or 0 .25 W.
20 8 Voice over 8 02. 11
13
Regulatory Considerations for Vo8 02. 11
Networks
An objection often raised about Vo8 02. 11 applications is that because the spec-
trum used by 8 02. 11 (2. 4 GHz ... use of Vo8 02. 11 as a means of
bypassing incumbent telephone service providers.
Current Regulatory Environment for 8 02. 11
The Vo8 02. 11 specification is VoIP over 8 02...
Voic 802.11e over phần 10 pot
... 116–17
IEEE 8 02. 11
8 02. 11a, 173
8 02. 11b, 23 , 173
8 02. 11e, 150
8 02. 11g, 173–74
architecture, 19 23
BSS, 14, 19, 20
carrier multiplexing, 13
components, 21 22
conclusion, 23 24
DCF, 18
DSSS, 11
ESS, 21
external ... multiple-access/collision
avoidance (CSMA/CA), 14, 19
Case studies, 21 7 23
education, 21 9 21
financial services, 22 1 22
manufacturing and war...