1. Kommunikatsiooniteenuste arendus IRT0080
Loeng 2 Avo Ots telekommunikatsiooni õppetool,
TTÜ raadio- ja sidetehnika inst.

2. Every machine transparently connected to every other
The Internet
Every machine transparently connected to every other

3. Piirkonnad ja piirpinnadT T T GW
SCN GW GW GK
MCU
Packet Network T T

4. The Problem
only nodes on the same physical/link layer network could communicate

5. Solution
Gateways

6. Classification of Multiple Access Protocols
Contention-based
Conflict-free
Random access
Collision resolution
ALOHA,
CSMA,
BTMA,
ISMA, etc
TREE,
WINDOW, etc
FDMA,
TDMA,
CDMA,
Token Bus,
DQDB, etc
BTMA: Busy Tone Multiple Access
ISMA: Internet Streaming Media Alliance
DQDB: Distributed Queue Dual Bus

7. Channel Sharing Techniques
Static Channelization
Channel Sharing Techniques
Scheduling
Dynamic Medium Access Control
Random Access

8. Throughput
0.368 S
Slotted Aloha
0.184
Aloha G

9. Vastastikused häired

10. Kvaliteet IP-võrgu kaudu
(LAN)
Router
Peakorter
Harukontor
(WAN)
QoS

11. Network structure (TUT)
public access networks (PAN) isolated from other networks in the edge routers
access from PAN to Internet controlled by access controllers
department ”intranets” may be protected with access control lists / filters in the edge routers
VLANs are used to separate access controllers to own access controller segment
public access network is considered a hostile network like the Internet
access
controller
Internet
Main house
”intra”
networks
TUT core
network
Main house
public access
network
public access networks (PAN) isolated from other networks in the edge routers
access from PAN to Internet controlled by access controllers
department ”intranets” may be protected with access control lists / filters in the edge routers
VLANs are used to separate access controllers to own access controller segment
public access network is considered a hostile network like the Internet
Tietotalo
public access
network
Tietotalo
”intra” networks

12. Network elements (TUT)
TUT core
network
Internet
department x
”intranet”
department y
”intranet”
VPN
terminator
Access
Controllers
public
access zone e.g. teamwork room
IPSEC/VPN secured
access to department
”intranet”
access zone consists of several access points preferably in the same IP network
IPSEC/VPN secured access also available from the public access zone
Public Access also available from the combined employee/public access zone
The same radio network is used to deliver services to both the employees and the guests/students.
The goal is to have no overlapping networks, instead one combined radio network providing coverage to all.
combined department employee/public
access zone
Nonencrypted filtered access to Internet
public
access zone e.g lecture hall

13. Sidesüsteemi mõjutavad
Fraud
Hacker
Internet
VPN
Fraud
Interception
Fraud
Viruses