In a data communication network, a communication network consists of routers, switches, firewalls, access controllers (ACs), access points (APs), PCs, network printers, and servers.
Switches
S5700-28TP-LI-AC
S7706
On a campus network, a switch is the device closest to end users and is used to connect terminals to the campus network. Switches at the access layer are usually Layer 2 Switches and are also called Ethernet Switches. Layer 2 refers to the data link layer of the TCP/IP reference model.
The Ethernet switch can implement the following functions: data frame switching, access of end user devices, basic access Security functions, and Layer 2 link redundancy.
Broadcast domain: A set of nodes that can receive broadcast packets from a node.
Routers
AR1220F
NE20E-S4
Routers are network-layer devices that forwards data packets on the Internet. Based on the destination address in a received packet，a router selects a path to send the packet to the next router or destination. The last router on the path is responsible for sending the packet to the destination host.
Routers can implement the following functions:
l Implementing communication between networks of the same type or different types
l Isolating broadcast domains
l Maintaining the routing table and running routing protocols
l Selecting routes and forwarding IP packets
l Implementing WAN access and network address translation
l Connecting Layer 2 networks established through switches
Firewalls
USG6630
Firewalls are network security devices used to ensure secure communication between two networks. It monitors，restricts and modifies data flows passing through it to shield information，structure，and running status of internal networks from the public network.
Firewalls can implement the following functions:
l Isolating networks of different security levels
l Implementing access control (using security policies) between networks of different security levels
l Implementing user identity authentication
l Implementing remote access
l Supporting data encryption and VPN services
l Implementing network address translation
l Implementing other security functions
Wireless devices
In a broad sense, WLAN is a network that uses radio waves, laser and infrared signals to replace some or all transmission media in a wired LAN. Common Wi-Fi is a WLAN technology based on the IEEE 802.11 family of standards.
On a WLAN, common devices include fat APs, fit APs, and ACs.
APs
AP4050DE AirEngine 8760R-X1
n Generally, it supports the fat AP, fit AP, and cloud-based management modes. You can flexibly switch between these modes based on network planning requirements.
n Fat AP: lt is applicable to homes. It works independently and needs to be configured separately. lt has simple functions and low costs.
n Fit AP: It applies to medium- and large-sized enterprises. It needs to work with the AC and is managed and configured by the AC.
n Cloud-based management: It applies to small- and medium-sized enterprises. lt needs to work with the cloud-based management platform for unified management and configuration. lt provides various functions and Supports plug-and-play.
l ACs
AC6005-8
n lt is generally deployed at the aggregation layer of the entire network to provide high-speed, secure, and reliable WLAN services.
n The AC provides wireless data control services featuring large capacity, high performance, high reliability, easy installation, and easy maintenance. It features flexible networking and energy saving.
