Voic 802 11e over phần 1 docx
Voic 802.11e over phần 1 docx
... Networks 14 1
QoS in 802. 11 14 3
Legacy 802. 11 MAC 14 3
DCF 14 4
PCF 14 8
Conclusion 15 3
References 15 3
9 Engineering Vo802 .11 Networks for Maximum QoS 15 5
QoS on Vo802 .11 Networks 15 5
Measuring Voice ... Range of Options 11 3
802. 11 Security Measures Beyond WEP 11 4
Wi-Fi Protected Access 11 4
802. 1x and EAP Advanced Security 11 5
x
Voice over 802. 11
compl...
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 .12 5 4.8 Waveform
G.7 21
G.723
G.726
16 , 24, 32, 40 0 .12 5 4.2
G.728 16 2.5 4.2
G.729 8 10 4.2
G.723 .1 ... are usually configured in multiples of T1 or E1 cards
in a single chassis that interface with the trunk side of the PBX. The T1 trunks
64 Voice over 802. 11
[8] Internet En...
Voic 802.11e over phần 5 docx
... performance and
12 0 Voice over 802. 11
11 2 Voice over 802. 11
Access point
Vo802 .11
p
hones
❘❙❚
❘❙❚
❘❙❚
❘❙❚
❘❙❚
❘❙❚
❘❙❚
❘❙❚
Internet
Router
IP phones
IP-PBX DMZ
server
Firewall
Hub
Figure 7 .12 Wireless ... at 0 again.
10 2 Voice over 802. 11
802. 11 access pointVo802 .11 phone
❘❙❚
❘❙❚
❘❙❚
❘❙❚
❘❙❚
❘❙❚
❘❙❚
❘❙❚
Intr
ude
r
Figure 7.2 Interception in a network.
How Kerberos...
Voic 802.11e over phần 2 pps
... a structured view of the 802. 11 parameters. The formal specification of the
802. 11 MIB is Annex D of the 802. 11 specification. The 802. 11 MIB was
designed by the 802. 11 working group [5, p. 383].
DCF
The ... and
then enters into a random back-off procedure (Figure 2.3). This prevents
18 Voice over 802. 11
16 Voice over 802. 11
Table 2.2 (continued)
Mac Service Descri...
Voic 802.11e over phần 4 pdf
... power, the range of 802. 11 is extended to
tens of miles [1] .
78 Voice over 802. 11
VoIP media
g
atewa
y
PSTN
IP network
Softswitch
802. 11 a/b/g
Vo802 .11
PDA
Vo802 .11
phone
Vo802 .11
laptop
Wireless ... to
point. The rollout of the 802. 16 MAN protocol allows the extension of
802. 11 b and associated wireless protocols over a wide geographic area. By
94 Voice over 802...
Voic 802.11e over phần 6 ppt
... work with all possible 802. 11 physical layers
(original 802. 11 , 802. 11 , 802. 11 a, and 802. 11 g). The following sections
describe QoS efforts in 802. 11 and the mechanisms in 802. 11 e that are
designed ... recently approved
802. 11 e, which is backward compatible with other variants of 802. 11 , which
means that improvements in QoS contained in 802. 11 e can be...
Voic 802.11e over phần 7 doc
... Vo802 .11 Networks for Maximum QoS 16 1
Which 802. 11 Protocols Are Best for Which Vo802 .11 Applications?
Four primary standards-based protocols are currently available: 802. 11 ,
802. 11 b, 802. 11 a, ... Networks 17 7
1
1
1
6
6
6
11
11
11
Figure 10 .4 A 3-to -1 reuse pattern. (
From:
[3]. © 2002 Neeli Prasad and Anand Prasad.
Reprinted with permission.)
802. 11 phone...
Voic 802.11e over phần 8 pdf
... 0.25W.
208 Voice over 802. 11
13
Regulatory Considerations for Vo802 .11
Networks
An objection often raised about Vo802 .11 applications is that because the spec-
trum used by 802. 11 (2.4 GHz for 802. 11 b ... use of Vo802 .11 as a means of
bypassing incumbent telephone service providers.
Current Regulatory Environment for 802. 11
The Vo802 .11 specification is VoIP over 802...
Voic 802.11e over phần 9 ppsx
... legally operating
Part 15 users. Table 13 .2 lists the 802. 11 b spectrum bands. This is stated in Part
15 .5 (b) and (c).
210 Voice over 802. 11
Table 13 .1
Spectrum Allocation for 802. 11 and Cousers
Part/Use
Starting
Gigahertz
Ending
Gigahertz
Part ... throughout the
building to ensure optimal coverage.
Economics of Vo802 .11 Networks 2 21
14
Economics of Vo802 .11 Networks...
Voic 802.11e over phần 10 pot
... authenticators, 11 8
encapsulation and, 11 7
integration, 11 7
network port authentication and, 11 6 17
IEEE 802. 11
802. 11 a, 17 3
802. 11 b, 23, 17 3
802. 11 e, 15 0
802. 11 g, 17 3–74
architecture, 19 –23
BSS, 14 , 19 , ... 50–52
QPSK, 11
Quality of service (QoS), 77–78, 79
in 802. 11 , 14 3
factors affecting, 16 0
importance on 802. 11 networks, 14 0– 41...