Cisco C921-4P Full Product Description

1. Short Overview

Suffix Breakdown

• C921: Base dual-Gigabit Ethernet wired router platform of Cisco 900 Series ISR
• 4: 4-port integrated Gigabit LAN switch
• P: PoE support on all LAN ports (IEEE 802.3af, total 60W PoE power budget)

Core Differentiators

1. vs LTE variant C921-4PLTExx: C921-4P has no embedded CAT4 LTE cellular modem, only dual copper GE WAN for fixed-line Metro Ethernet deployments.
2. vs DSL models C926-4P / C927-4PM: Those integrate VDSL2/ADSL2+ copper DSL modems; C921-4P is pure Ethernet without xDSL hardware.
3. vs older C891F-K9 ISR G2: C921-4P runs modern IOS XE firmware with native SD-WAN support, smaller compact form factor, internal power supply instead of external AC adapter, simplified port layout and optimized low-power design.
4. vs industrial rugged routers: C921-4P is commercial indoor desktop hardware with standard temperature range, not hardened for vehicle, railway or extreme outdoor shock/vibration environments.

2. Hardware Interface & Performance Specifications

Dual Redundant Gigabit Ethernet WAN Ports (Automatic Failover Supported)

4-Port Full Gigabit PoE Managed LAN Switch

• 802.1Q VLAN tagging, port isolation, static MAC port security, dedicated DMZ port assignment
• Broadcast storm control, SPAN traffic monitoring, LACP link aggregation, Smartport macros
• Per-port CoS marking, port speed limiting, private VLAN segmentation

Management & Auxiliary Ports

1. Single USB 2.0 Type-A host port: External flash storage for offline config backups, log archiving, EEM automation scripts and device zero-touch provisioning files
2. Integrated internal power supply unit, no separate external AC adapter required
3. Hardware reset button, Kensington anti-theft lock slot for physical equipment protection
4. Embedded RTC real-time clock for accurate timestamping of security logs, certificates and network event triggers

Memory & Storage

• DRAM: 1 GB system memory, supports up to 50 concurrent IPsec VPN tunnels, SD-WAN traffic forwarding, inline threat defense and full PoE LAN processing
• Flash: 256 MB onboard flash storage; factory preloaded IOS XE Universal Advanced Security image, minimum supported release 16.x IOS XE

Front Panel LED Status Indicators

Physical & Power Parameters

• Form factor: Compact metal desktop chassis, optional wall-mount bracket available
• Dimensions (H × W × D): 44 mm × 240 mm × 180 mm
• Weight: ~1.2 kg (2.6 lbs) with integrated internal power supply
• Built-in internal power supply, universal 100–240V AC mains input, no separate external power brick needed
• Typical maximum power consumption: 22 W under dual GE WAN + all 4 PoE LAN ports full load
• Ingress protection: IP20, only suitable for dry indoor commercial office environments

Environmental Operating Specifications

• Operating temperature: 0°C ~ +40°C (32°F ~ 104°F); performance degrades 1.5°C per 1000 m altitude above 3000 m
• Storage temperature: -20°C ~ +65°C (-4°F ~ 149°F)
• Relative humidity: 10%–85% RH non-condensing
• Maximum operating altitude: 3,000 m (10,000 ft)

3. Hardware Acceleration & Security Engine

• Dedicated onboard crypto co-processor fully offloads IPsec, IKEv2 and SSL VPN encryption traffic, eliminating CPU bottlenecks under heavy concurrent remote access and site-to-site tunnel loads
• Permanent integrated security license suite enables full enterprise encryption stack: AES-128/192/256, 3DES, DES, SHA-1/SHA-2, IKEv1/IKEv2 static tunnels, Easy VPN remote access and DMVPN dynamic hub-spoke tunnels
• Native traffic isolation filters to segregate corporate staff LAN, PoE camera/VoIP subnet and untrusted internet via independent VLAN zoning

4. Cisco IOS XE Advanced Security & SD-WAN Feature Suite

Dual GE WAN Redundancy & Metro Ethernet Routing

• Cisco Express Forwarding (CEF), static routing, RIPv1/v2, OSPF, EIGRP, BGP, GRE/MGRE tunnel encapsulation, complete IPv4/IPv6 dual-stack support
• Automatic policy-based failover logic between primary and secondary copper GE WAN links via HSRP/VRRP/MHSRP
• Metro Ethernet OAM, E-LMI, 802.3ah link fault monitoring for end-to-end carrier circuit SLA tracking
• Policy-Based Routing (PBR), multi-NAT pools, PAT overload for logical segmentation of PoE-powered IoT devices and standard wired endpoints
• DHCP server/relay/client, DNS proxy, dynamic DNS, IP SLA active link performance monitoring

Unified Enterprise Threat Security Suite

• Zone-Based Stateful Inspection Firewall (ZBFW) to isolate internal corporate LAN, PoE device subnet, DMZ and untrusted internet traffic zones
• Cisco IOS XE Next-Generation Intrusion Prevention System (NGIPS), cloud URL filtering, deep NBAR2 application control for HTTP, FTP, IM, video conferencing and mainstream business applications
• AAA authentication via TACACS+ / RADIUS, 802.1X port authentication available on all 4 Gigabit PoE LAN ports
• Secure management only: SSHv2, HTTPS, SNMPv3; plaintext Telnet disabled by factory default
• Granular access control lists (ACLs), static MAC address port lockdown on Gigabit switch ports, anti-spoofing and DDoS protection

SD-WAN & QoS Bandwidth Optimization

• Native Cisco SD-WAN Viptela integrated functionality for multi-path intelligent traffic steering, application-aware routing over dual GE WAN links
• WFQ, CBWFQ, LLQ low-latency queuing mechanisms for voice, video surveillance, POS payment and industrial SCADA real-time traffic prioritization
• NBAR2 deep packet inspection to classify and prioritize business-critical workloads over metered Metro Ethernet circuits
• RTP/TCP header compression, traffic shaping and policing to control leased-line bandwidth consumption and avoid overage charges
• PoE QoS scheduling to guarantee stable power and bandwidth priority for mission-critical IP cameras and VoIP handsets

Remote Management & Automation

• Cisco Zero-Touch Provisioning (ZTP) for mass standardized deployment of enterprise branches and service provider Metro Ethernet CPE
• Cisco IOS Embedded Event Manager (EEM): Scriptable triggers for WAN link loss, PoE power faults and USB storage events with email/SNMP alert notifications
• SNMP v2c/v3, remote syslog logging, IP SLA end-to-end link performance telemetry
• Compatible with Cisco Configuration Professional (CCP), Cisco DNA Center Lite and vManage SD-WAN controller for unified single-pane-of-glass remote monitoring of routing, security, PoE and WAN subsystems
• GOLD non-disruptive onboard diagnostics for continuous remote hardware health checks of dual GE WAN, PoE LAN and USB management interfaces

5. Typical Deployment Scenarios

1. Small Retail Kiosk Dual-Gigabit PoE Secure Gateway
   Dual copper GE WAN ports deliver redundant Metro Ethernet broadband for POS transaction traffic; 4-port full PoE LAN switch powers payment terminals, VoIP phones and on-site IP surveillance cameras. VLAN segmentation isolates sensitive payment infrastructure from guest device traffic, persistent IPsec DMVPN/SD-WAN tunnels transmit retail data securely back to central corporate data centers, zone firewall + NGIPS block external network intrusion risks.
2. Service Provider Managed Metro Ethernet Business CPE
   Uniform compact hardware platform enables ISPs to deliver dual redundant Gigabit Ethernet managed broadband services to small enterprise subscribers. Centralized ZTP mass deployment and remote SNMP/vManage monitoring support bundled managed security, PoE and SD-WAN networking service packages.
3. Remote Small Office SD-WAN Branch Router
   Dual GE WAN redundancy meets enterprise business continuity requirements, integrated PoE eliminates separate power injectors for cameras and VoIP handsets, full EIGRP/BGP and native SD-WAN support enable seamless intelligent multi-path traffic steering to corporate headquarters.
4. Campus Remote Building PoE IoT Edge Router
   PoE LAN ports connect IP cameras, access control hardware and environmental monitoring sensors; dual GE WAN links provide primary and backup backhaul to campus core network, automatic failover ensures uninterrupted video and sensor data transmission during circuit outages.
5. Compact Teleworker Small Office Secure VPN Concentrator
   Deployed at remote employee sites with dual Metro Ethernet circuits, dual GE redundant transport delivers stable encrypted Easy VPN/SD-WAN connectivity to corporate headquarters, PoE ports power home office IP cameras and VoIP equipment, integrated unified security services defend all wired Gigabit endpoints against malware and unauthorized internet access.

6. Standard Package Contents of C921-4P

Separately Sold Optional Accessories

• RJ45 rollover console cable for local CLI configuration
• USB flash storage drives for log archiving and offline configuration backup
• CAT5e/CAT6 Ethernet patch cords for LAN and dual GE WAN connections

Software Licensing Information

• Permanent integrated security & crypto license included; no additional purchase required for IPsec, AES encryption, firewall and NGIPS threat defense features
• All core routing, dual-GE WAN failover, SD-WAN intelligent routing, PoE power management, QoS, ZTP and 4-port Gigabit managed switch features are fully included in the base IOS XE universal image; no extra paid feature licenses needed
• No wireless AP or cellular modem license applicable (corresponding hardware is omitted from this pure wired Ethernet PoE SKU)

Short Commercial Catalog Summary for Quotation