Feature Description Capacity in millions of packets per second (mpps) (64-byte packets) 41.66 Switching capacity in gigabits per second (Gbps) 56.0 Total system ports 28 Gigabit Ethernet RJ-45 ports 24 Gigabit Ethernet Packet buffer 1.5 MB Unit dimensions (W x D x H) 445 x 240 x 44 mm (17.5 x 9.45 x 1.73 in) Layer 2 switching VLAN Support for up to 255 active VLANs simultaneously Port-based and 802.1Q tag-based VLANs Management VLAN Guest VLAN Voice VLAN Voice traffic is automatically assigned to a voice-specific VLAN and treated with appropriate levels of QoS. Voice Services Discovery Protocol (VSDP) delivers networkwide zero-touch deployment of voice endpoints and call control devices Layer 3 routing IPv4 routing Wire-speed routing of IPv4 packets Up to 32 static routes and up to 16 IP interfaces IPv6 routing Wire-speed routing of IPv6 packets Layer 3 interface Configuration of Layer 3 interface on physical port LAG VLAN interface or loopback interface Security Secure Sockets Layer (SSL) SSL encrypts all HTTPS traffic allowing secure access to the browser-based management GUI in the switch Secure Shell (SSH) Protocol SSH is a secure replacement for Telnet traffic. Secure Copy (SCP) also uses SSH. SSH v1 and v2 are supported. IEEE 802.1X (authenticator role) Remote Authentication Dial-In User Service (RADIUS) authentication guest VLAN single/multiple host mode and single/multiple sessions STP loopback guard Provides additional protection against Layer 2 forwarding loops (STP loops) Secure Core Technology (SCT) Ensures that the switch will receive and process management and protocol traffic no matter how much traffic is received Secure Sensitive Data (SSD) A mechanism to manage sensitive data (such as passwords keys and so on) securely on the switch populating this data to other devices and secure autoconfig. Access to view the sensitive data as plain text or encrypted is provided according to the user-configured access level and the access method of the user Trustworthy systems Trustworthy systems provide a highly secure foundation for Cisco products Run-time defenses (Executable Space Protection [X-Space] Address Space Layout Randomization [ASLR] Built-In Object Size Checking [BOSC]) Port security Ability to lock source MAC addresses to ports and limit the number of learned MAC addresses RADIUS Supports RADIUS authentication for management access. Switch functions as a client. Storm control Broadcast multicast and unknown unicast DoS prevention Denial-of-Service (DoS) attack prevention Multiple user privilege levels in CLI Level 1 7 and 15 privilege levels Access Control Lists (ACLs) Support for up to 512 rules Drop or rate limit based on source and destination MAC VLAN ID or IPv4 or IPv6 address IPv6 flow label protocol port Differentiated Services Code Point (DSCP)/IP precedence TCP/UDP source and destination ports 802.1p priority Ethernet type Internet Control Message Protocol (ICMP) packets IGMP packets TCP flag; ACL can be applied on both ingress and egress sides Time-based ACLs supported Flash 256 MB CPU 800 MHz ARM DRAM 512 MB Environmental Power 100 to 240V 50 to 60 Hz internal universal: CBS250-16T-2G CBS250-16P-2G CBS250-24T-4G CBS250-24PP-4G CBS250-24P-4G CBS250-24FP-4G CBS250-48T-4G CBS250-48PP-4G CBS250-48P-4G CBS250-24T-4X CBS250-24P-4X CBS250-24FP-4X CBS250-48T-4X CBS250-48P-4X 100 to 240V 50 to 60 Hz external: CBS250-8T-D CBS250-8PP-D CBS250-8T-E-2G CBS250-8PP-E-2G CBS250-8P-E-2G CBS250-8FP-E-2G Certification UL (UL 62368) CSA (CSA 22.2) CE mark FCC Part 15 (CFR 47) Class A Operating temperature 32° to 122°F (0° to 50°C) for CBS250-8T-D and CBS250-8PP-D 23° to 122°F (-5° to 50°C) for other models Storage temperature -13° to 158°F (-25° to 70°C) Operating humidity 10% to 90% relative noncondensing Storage humidity 10% to 90% relative noncondensing Warranty Limited lifetime