The S6720-LI series switches (S6720-LI) are next-generation simplified 10 GE fixed switches and can be used as 10 GE access switches on campus networks and data center networks.
The S6720-LI provides line-rate 10 GE access ports and 40 GE uplink ports. In addition, the S6720-LI delivers a wide variety of services, comprehensive security control policies, and various QoS features to help customers build scalable, reliable, manageable, and secure campus and data center networks.
Product features and highlights
High-density 10 GE access and 40 GE uplink
To provide sufficient bandwidth for users, more and more servers use 10G network adapters. The S6720-LI has the highest density of 10 GE ports and largest switching capacity among counterpart switches. Each S6720-LI provides up to 32 line-rate 10 GE ports and two line-rate QSFP+ ports.
Ports of the S6720-LI support GE access and 10 GE access and can identify optical module types, maximizing the return on investment and allowing users to flexibly deploy services.
Comprehensive security control policies
The S6720-LI provides multiple security measures to defend against Denial of Service (DoS) attacks, as well as attacks against networks or users. DoS attacks include SYN flood, Land, Smurf, and ICMP flood attacks. Attacks to networks refer to STP BPDU/root attacks. Attacks to users include bogus DHCP server attacks, man-in-the-middle attacks, IP/MAC spoofing attacks, and DHCP request flood attacks. DoS attacks that change the CHADDR field in DHCP packets are also attacks against users.
The S6720-LI supports DHCP snooping, which generates user binding entries. DHCP snooping discards invalid packets that do not match any binding entries, such as ARP spoofing packets and IP spoofing packets. This prevents hackers from using ARP packets to initiate attacks on campus networks. DHCP snooping trusted ports can be specified to ensure that users connect only to the authorized DHCP server.
The S6720-LI supports strict ARP learning. This feature prevents ARP spoofing attackers from exhausting ARP entries so that users can connect to the Internet normally. The S6720-LI supports IP source check to prevent DoS attacks caused by MAC address spoofing, IP address spoofing, and MAC/IP spoofing.
The S6720-LI supports centralized MAC address authentication and 802.1X authentication. It authenticates users based on statically or dynamically bound user information such as the user name, IP address, MAC address, VLAN ID, port number, and flag indicating whether antivirus software is installed. VLANs, QoS policies, and ACLs can be applied to users dynamically.
The S6720-LI can limit the number of MAC addresses learned on a port to prevent attackers from exhausting MAC address entries by using bogus source MAC addresses. This function minimizes packet flooding that occurs when MAC addresses of users cannot be found in the MAC address table.
Comprehensive reliability mechanisms
The S6720-LI supports MSTP multi-process that enhances the existing STP, RSTP, and MSTP implementation. This function increases the number of MSTIs supported on a network. It also supports enhanced Ethernet reliability technologies such as Smart Link and RRPP, which implement millisecond-level protection switchover and ensure network reliability. Smart Link and RRPP both support multi-instance to implement load balancing among links, improving bandwidth use efficiency.
The S6720-LI supports enhanced trunk (E-trunk). A CE can be dual-homed to two PEs through Eth-Trunk links. This implements inter-device link aggregation and link load balancing, and greatly improves reliability of access devices.
The S6720-LI supports the Smart Ethernet Protection (SEP) protocol, a ring network protocol applied to the link layer of an Ethernet network. SEP can be used on open ring networks and provides millisecond-level switchover to ensure nonstop services. SEP features simplicity, high reliability, fast switchover, easy maintenance, and flexible topology, facilitating network planning and management.
The S6720-LI supports G.8032, also called Ethernet Ring Protection Switching (ERPS). ERPS is based on traditional Ethernet MAC and bridging functions. It uses the mature Ethernet OAM and Ring Automatic Protection Switching (Ring APS or R-APS) technologies to implement millisecond-level protection switchover on Ethernet. ERPS supports multiple services and provides flexible networking, reducing the OPEX and CAPEX.
The S6720-LI supports VRRP. Two S6720-LIs can form a VRRP group to ensure nonstop and reliable communication. Multiple equal-cost routes to an upstream device can be configured on the S6720-LI to provide route redundancy. When an active route is unreachable, traffic is switched to a backup route.
Various QoS control mechanisms
The S6720-LI implements complex traffic classification based on packet information such as the 5-tuple, IP preference, ToS, DSCP, IP protocol type, ICMP type, TCP source port, VLAN ID, Ethernet protocol type, and CoS. ACLs can be applied to inbound or outbound direction to filter packets. The S6720-LI supports a flow-based two-rate three-color CAR. Each port supports eight priority queues and multiple queue scheduling algorithms such as WRR, DRR, PQ, WRR + PQ, and DRR + PQ. All of these ensure the quality of voice, video, and data services.
The S6720-LI supports intelligent Stack (iStack) and virtualizes multiple switches into one logical switch. A port of the S6720-LI can be configured as a stack port using a command for flexible stack deployment. The distance between stacked switches is further increased when the switches are connected with optical fibers. Compared with a single device, iStack has advantages on scalability, reliability, performance, and overall architecture. A new switch can join a stack to increase the system capacity or replace a faulty member switch without interrupting services. Compared with stacking of modular switches, the iStack function can increase system capacity and port density with no restriction of the hardware architecture. Multiple devices in a stack can be considered as one logical device. These switches can be managed using a single IP address, which greatly reduces system expansion and O&M costs.
The S6720-LI supports automatic configuration, plug-and-play, deployment using a USB flash drive, and batch remote upgrade. These capabilities simplify device management and maintenance, and greatly reduce maintenance costs.
The S6720-LI supports SNMP v1/v2/v3 and provides flexible methods for managing and maintaining devices, such as CLI and Web NMS. The NQA function helps users with network planning and upgrades. In addition, the S6720-LI supports NTP, SSH v2, HWTACACS, RMON, log hosts, and port-based traffic statistics.
The S6720-LI supports GVRP, which dynamically distributes, registers, and propagates VLAN attributes to reduce the manual configuration workloads of network administrators and ensure correct VLAN configuration.
The S6720-LI supports MUX VLAN that isolates Layer 2 traffic between ports in a VLAN. MUX VLAN defines principal VLANs and subordinate VLANs. Subordinate VLANs can communicate with the MUX VLAN but cannot communicate with each other. This function prevents communication between network devices connected to certain ports or port groups but allows the devices to communicate with the default gateway. MUX VLAN is usually used on an enterprise intranet to isolate user ports from each other but allow them to communicate with server ports.
Complying with IEEE 802.3ah and 802.1ag, the S6720-LI supports point-to-point Ethernet fault management and can detect faults in the last mile of an Ethernet link to users. Ethernet OAM improves the Ethernet network management and maintenance capabilities and ensures a stable network.
Various IPv6 features
The S6720-LI supports various IPv6 routing protocols including RIPng and OSPFv3. It uses the IPv6 Neighbor Discovery Protocol (NDP) to manage packets exchanged between neighbors. It also provides the Path MTU Discovery (PMTU) mechanism to select a proper MTU on the path from the source to the destination, optimizing network resources and obtaining the maximum throughput.
Networking and applications
Data center networks
As shown in the following figure, the S12700 agile switches function as core switches in a data center and use firewall and load balancer cards to ensure security and perform load balancing. The S6720-LIs function as access switches and provide high-density 10 GE ports to connect to 10G servers.
The S6720-LI series switches can be used as access or aggregation switches on small and medium-sized campus networks and provide high-density line-rate 10 GE ports, rich service features, and comprehensive security mechanism. All of those make the S6720-LI cost effective on campus networks.