What is Open System Interconnection (OSI) model ?
- is a conceptual framework used to understand and standardize how data is transmitted over a network.
Physical (bits are transmitted over the wire)
Data Link (data is framed and error-checked)
Network (data is routed)
Transport (data is segmented and reassembled)
Session (connection is established)
Presentation (data is formatted)
Application (data is created)
List the 7 OSI model.
Layer 1: Physical Layer
Protocols: RJ-45, Wi-Fi, fiber optics
Functions: Bit transmission, reception, signaling
Layer 2: Data Link Layer
Protocols: Ethernet, Wi-Fi, PPP
Functions: Framing, error detection, flow control
Layer 3: Network Layer
Protocols: IP, ICMP, IGMP
Functions: Routing, addressing, congestion control
Layer 4: Transport Layer
Protocols: TCP, UDP, SCTP
Functions: Segmentation, reassembly, error detection
Layer 5: Session Layer
Protocols: NetBIOS, SSH
Functions: Session establishment, maintenance, termination
Layer 6: Presentation Layer
Protocols: SSL, TLS, MIME
Functions: Data encryption, compression, formatting
Layer 7: Application Layer
Protocols: HTTP, FTP, SMTP, DNS
Functions: Data formatting, encryption, compression
What is a multilayer switch ?
- MLS is a network switch that operates at multiple layers of the OSI model, specifically:
- Layer 2 (Data Link Layer): MLS switches at this layer, using MAC addresses to forward data packets.
- Layer 3 (Network Layer): MLS switches at this layer, using IP addresses to route data packets.
- Layer 4 (Transport Layer): Some MLS switches operate at this layer, using TCP/UDP ports to make forwarding decisions
- MS combine the functions of:
- Layer 2 switches: Forwarding data packets based on MAC addresses.
- Routers: Routing data packets based on IP addresses.
What is a wireless controller ?
- WC is a network device that manages and controls wireless access points (APs) in a wireless local area network (WLAN). It’s also known as a wireless LAN controller or WLAN controller.
What is roaming ?
- Roaming in networking refers to the ability of a wireless device to maintain its network connection while moving from one wireless access point (AP) to another.
List 3 types of roaming .
- Intra-controller roaming: Roaming between APs managed by the same controller.
- Inter-controller roaming: Roaming between APs managed by different controllers.
- Inter-subnet roaming: Roaming between APs on different subnets.
What is a Load Balancer in networking.
What are IPS and IDS ?
What is UTM appliance ?
What is Next Gen Firewall (NGFW) ?
