Cisco Catalyst 8500L C8500L-8S4X Architecture and 1GE 10GE Port Capacity

The Cisco Catalyst 8500 Series Edge Platforms are high-performance WAN and cloud-edge routers designed for high-throughput routing, IPsec, SD-WAN services, multi-layer security, cloud connectivity, and programmable IOS XE operation. The family includes three Catalyst 8500 Edge Platform models and one Catalyst 8500L Edge Platform:

• C8500-20X6C
• C8500-12X4QC
• C8500-12X
• C8500L-8S4X

The Catalyst 8500 models use the third-generation Cisco Quantum Flow Processor and support interfaces from 1GE through 100GE. The Catalyst 8500L uses an x86-based architecture with flow-based forwarding and dynamic allocation of processing cores between data-plane, I/O, and service-plane functions.

Platform selection

The C8500-20X6C is the highest-capacity model and provides 800 Gbps of total interface bandwidth with all interfaces enabled simultaneously. The C8500-12X4QC supports up to 240GE of ports simultaneously, subject to its port-mode and bay restrictions.

The C8500L-8S4X is the compact member of the family. It provides four 1/10GE ports and eight 1GE ports, with an x86 architecture intended to provide higher service performance than the physical port count alone would suggest.

Port density and operating modes

The C8500-20X6C supports these representative configurations:

• 20 x 1GE
• 20 x 10GE
• 6 x 40GE plus 20 x 10GE
• 6 x 100GE plus 20 x 10GE
• 6 x 40/100GE plus 20 x 10GE
• 6 x 40/100GE plus 20 x 1/10GE

The C8500-12X4QC supports:

• 12 x 1GE
• 12 x 10GE
• 4 x 40GE plus 8 x 10GE
• 2 x 100GE
• 1 x 100GE plus 3 x 40GE
• 1 x 100GE plus 1 x 40GE plus 8 x 10GE
• 1 x 100GE plus 12 x 10GE
• 12 x 10GE plus 3 x 40GE

When Bay 1 is configured in 100GE mode on the C8500-12X4QC, no other ports in Bay 0 or Bay 1 are available. Four-port 10GE breakout from QSFP 40G ports can produce 24 x 10GE interfaces, but this configuration is not supported in SD-WAN mode.

Performance and scale

SD-WAN controller mode

IMIX represents an average packet size of 352 bytes. The published throughput figures are maximum values and should not be treated as a universal design rate for every combination of encryption, QoS, firewalling, NAT, DPI, application visibility, and tunnel count.

For the C8500L-8S4X, published SD-WAN multi-layer security results are:

• Up to 5.9 Gbps for traffic consisting of 50 percent IQDF traffic and 50 percent DIA traffic with NAT, next-generation firewall, IPS, URL filtering, and AMP.
• Up to 4 Gbps for DIA traffic with NAT, next-generation firewall, IPS, URL filtering, and AMP.

IQDF includes IPsec, QoS, deep packet inspection, and Flexible NetFlow.

Autonomous mode

The C8500-20X6C is the appropriate selection where route scale, NAT scale, firewall sessions, and interface bandwidth are simultaneously high. The C8500-12X4QC provides a strong balance between 1RU density and high-speed uplink flexibility. The C8500L-8S4X should be selected when the service profile fits within its lower NAT, firewall, queue, and interface limits.

Architecture and software

The Catalyst 8500 models use a third-generation Quantum Flow Processor with hardware-accelerated encryption for IPsec and MACsec. The published data sheet states that these platforms provide up to five times the IPsec throughput of second-generation QFP devices.

The C8500L uses an x86-based platform architecture with:

• Flow-based forwarding to reduce overhead for stateful services.
• Dynamic core allocation between data-plane, I/O, and service-plane functions.
• Intel x86 control processing.
• Support for up to 64GB of DRAM.
• Optional 2TB M.2 NVMe storage.

Both autonomous IOS XE operation and controller-based Catalyst SD-WAN operation are supported. The software architecture includes routing, IPsec, QoS, firewall, NAT, NBAR, Flexible NetFlow, API support, and automation capabilities.

Autonomous-mode protocol support includes IPv4, IPv6, static routing, RIP, OSPF, EIGRP, BGP, IS-IS, MPLS, Layer 2 and Layer 3 VPN, EVPN, VXLAN, segment routing, multicast, HSRP, VRFs, LISP, BFD, MACsec, L2TPv3, PPPoE, GRE, VLAN, and broadband functions.

Controller mode adds OMP, Application Aware Routing, service insertion, traffic engineering, zero-trust functions, DTLS and TLS, NAT64, Cflowd, IPFIX export, Netconf over SSH, TrustSec and SDA inline SGT propagation, per-tunnel QoS, Direct Internet Access, SD-AVC, SaaS traffic steering, FEC, and multi-VRF support.

Minimum IOS XE requirements are:

ThousandEyes is natively integrated on eligible platforms with more than 8GB of DRAM and 8GB of bootflash or storage. Additional memory and storage may be required when the agent runs concurrently with containerized SD-WAN security services.

Memory, storage, and accessories

The C8500-20X6C includes 64GB of DRAM and a 480GB SSD as standard configuration elements. The C8500-12X and C8500-12X4QC include 16GB of DRAM by default and support 32GB or 64GB upgrades. These models use 32GB eUSB storage by default and support an optional 480GB M.2 SATA SSD.

The C8500L-8S4X includes 16GB of DRAM by default, supports 32GB and 64GB upgrades, and provides 16GB eUSB storage with a 32GB eUSB upgrade option. An optional 2TB M.2 NVMe SSD is available.

Power and resiliency

The platforms use high-efficiency dual power supplies by default for power redundancy. All models support software redundancy with two IOS XE processes operating on a single device in IOS XE routing mode.

The C8500-20X6C supports up to four power supply slots, with at least two power supplies required to be populated and powered. It supports N+1 redundancy and an option for N+2 redundancy.

The 1100W AC supply accepts 90 to 264 VAC at 50 to 60 Hz, provides 12V at 90A, and has 16ms output holdup. The 750W AC supply accepts 85 to 264 VAC at 47 to 63 Hz, provides 12V at 63A, and has 20ms output holdup. The 950W DC supplies accept -40 to -72V DC and provide 12V at 79A.

The C8500L AC supply accepts 85 to 264 VAC at 47 to 63 Hz and provides 400W output. The HV supply supports 85 to 305 VAC, 192 to 400V DC, and provides 500W output at 12V and 42A.

Presales power rules are straightforward:

1. Confirm the available facility input: standard AC, -48V DC, or high-voltage AC/DC.
2. Use separate power feeds where the installation requires feed-level resiliency.
3. Validate rack heat removal using maximum BTU/hr rather than typical power.
4. Size circuit protection and cabling for the selected supply input current.
5. Treat power supply redundancy and software redundancy as separate protections; neither replaces the other.

Physical, environmental, and acoustic specifications

Operating temperature is 32 to 104 degrees F, or 0 to 40 degrees C, for the C8500-20X6C and C8500-12X4QC. Storage temperature is -40 to 150 degrees F, or -40 to 70 degrees C. Operating relative humidity is 10 to 85 percent noncondensing. Nonoperating and storage humidity is 5 to 95 percent noncondensing.

The published environmental table lists NEBS criteria GR-1089 and GR-63, with an operating altitude range of -500 to 10,000 feet, or -152 to 3048 meters, for the applicable platform entries. Environmental values for the C8500-12X and C8500L-8S4X are not separately populated in the mechanical table beyond the listed platform data and should be validated against the installation requirements.

Acoustic specifications are:

These values are relevant to office-adjacent rooms, laboratories, and customer premises where acoustic limits apply. The C8500-20X6C has the highest published maximum sound levels and heat output.

Licensing, warranty, and services

All Catalyst 8500 Series Edge Platforms initially require a Cisco DNA Advantage Software subscription. Smart Licensing uses an organizational license pool managed through Cisco License Central and requires a Smart Account.

A valid ThousandEyes agent license is required to activate the ThousandEyes agent.

The standard hardware entitlement is a Cisco Limited One-Year Return To Factory Hardware Warranty.

Cisco Solution Support is the default and recommended support service for Catalyst 8000 platforms, but it is not mandatory. It may be replaced by another Cisco support service or partner service. For complete Solution Support entitlement, support must be ordered for both the Catalyst 8000 platform and the Cisco DNA Software for SD-WAN and Routing.

Cisco Subscription Embedded Software Support provides software troubleshooting assistance, online tools, web case submission, TAC access, and software library access for the Cisco DNA software. It does not provide hardware coverage. Hardware support must be purchased separately when embedded software support is used.

Ordering matrix

Platforms and subscriptions

Power supplies and spares

Memory and storage

Mounting, cooling, filtering, and asset accessories

Optics and transceiver compatibility should be selected from the platform-specific transceiver matrix. The published data sheet identifies the matrix but does not enumerate individual optic SKUs.