4.e- Wireless Networks Flashcards
Wi-Fi
Permits computers to communicate with each other wirelessly at high speeds over moderate distances from each other.
Wi-Fi standards
IEEE 802.11 standards
Wi-Fi Security
- Authentication :
- Access control
- Encryption with WEP, or WAP2 method. WEP is no longer used
- Network identifier- SSID
- Broadcast
- Signal strength
Subnet mask
A numeric value that determines which portion of an IP is used to identify the network and which portion is used to identify a station on the network
Transport Layer protocols
• TCP & UDP
•
Messaging protocols
- SMTP
- SMTPS
- POP
- IMAP
- NNTP
Session Protocols
- Telnet - does not encrypt
- rlogin - does not encrypt
- SSH - provides secure channel between two computers, with encrypted communication
- HTTP -used to transmit webpage contents
- HTTPS transports data between two servers- its like HTTP encrypted with SSL or TLS protocols
Firewall
Devise used to control which network packets are permitted to cross network boundaries.
Application firewall
Devise used to control packets being sent to an application server, blocking those that contain unwanted or malicious content.,
Can help to protect a web server from attacks such as SQL injection or buffer overflown
Proxy Server
Devise used to control end-user access to websites on the Internet. It typically controls access according to policy.
Layers
- Layer 4 switch : devise used to route packets to destinations based on TCP and UDP port numbers.
- Layer 4-7 switch : used to route packets to destinations based on their internal content.
sniffers
A software program that can be installed on a network =attached system , or a separate hard device, used to capture and analyze network traffic.
Client server
they consist of one or more central application servers, database servers, and business workstations.
