ISR4351/K9 – 3x1G RJ45/SFP Ports – 3 NIM + 2 SM-X Slots – ISR 4351 Branch Router
Why Layer23-Switch
Stocked, Shipped and Supported by One Team
Ships in 1 Business Day
In-stock orders leave our Hong Kong or U.S. warehouse within 1 business day after payment, with tracking by email.
LSCare Warranty
3years on enterprise equipment
Free CCIE Support
Certified engineers help before and after you buy. Reply within 1 business day by email or live chat.
Verify Before You Pay
100%factory-sealed
Get label and serial photos before shipment, and check every serial number with Cisco.
ISR4351/K9 Description
The ISR4351/K9 is a Cisco ISR 4351 integrated services router from the Cisco 4000 Family, built for branch offices that terminate several WAN circuits, voice trunks and service modules in one 2RU chassis. The router has three NIM slots and two SM-X slots, three onboard Gigabit Ethernet ports that each run as RJ-45 or SFP, 4 GB of DRAM and 200 Mbps of aggregate throughput, or 400 Mbps with a performance license. The chassis holds a single internal AC, DC or PoE supply and has no redundant power option.
Quick Specs
|
Parameter |
Specification |
|---|---|
|
Onboard WAN or LAN ports |
3 x 10/100/1000; each port runs as RJ-45 or SFP, one medium at a time |
|
Management port |
1 dedicated Gigabit Ethernet port |
|
Module slots |
3 NIM slots, 2 enhanced SM-X slots (or 1 double-wide SM-X) and 1 onboard ISC slot |
|
Aggregate throughput |
200 Mbps default; 400 Mbps with FL-4350-PERF-K9 |
|
DRAM |
4 GB, upgradable to 16 GB |
|
Default flash |
4 GB, upgradable to 16 GB |
|
Default power supply |
PWR-4450-AC 450W AC; 430W maximum system power |
|
Default PoE budget |
None; the default AC supply carries no endpoint PoE |
|
PoE with PWR-4450-POE-AC |
500W for endpoints, 990W platform maximum |
|
Front-panel PoE+ |
GE 0/0/0 and GE 0/0/1, 30.8W total from the internal PoE module |
|
Redundant power supply |
Not available |
|
Encryption without HSEC |
1,000 secure tunnels and 250 Mbps of crypto bandwidth |
|
Form factor |
2RU, 3.5 x 17.25 x 18.5 in |
Product Performance
Key Features
Each SM-X slot connects to the system at up to 10 Gbps and to other module slots at 1 Gbps. The pair can also hold one double-wide module instead, and SM-X-6X1G adds six dual-mode GE/SFP routed ports per slot.
Three NIM slots come standard, each with two 2 Gbps links. A carrier card turns an SM-X slot into a NIM slot, so a chassis built around NIM-24A asynchronous modules can hold five of them with SM-X-NIM-ADPTR carriers.
The router forwards 200 Mbps of aggregate traffic as shipped. FL-4350-PERF-K9, delivered remotely, doubles that to 400 Mbps with no hardware change; the separate boost license applies only to CEF forwarding over the onboard ports.
Ports GE 0/0/0 and GE 0/0/1 deliver 802.3at PoE+ from an internal PoE module, 30.8W in total, enough for one 30W device such as a cellular gateway. That budget is separate from the PoE power supply, which feeds up to 500W to integrated switch modules.
The internal supply accepts 100 to 240 VAC or, with PWR-4450-DC, -48 to -60 VDC at up to 437W. The chassis takes one supply at a time, and redundant power is not available on this model.
A PVDM4 sits in the internal ISC slot and handles conferencing, transcoding and media optimization, reaching 256 low-complexity channels on PVDM4-256. All three NIM slots and both SM-X slots stay free for interfaces.
Application Scenarios
A large branch running MPLS, broadband and a backup circuit lands each link on one of the three onboard Gigabit ports, with copper or fiber chosen port by port, and adds further WAN interfaces through the NIM slots.
In a data room or network operations area, the router can act as a 200-port terminal server, with three NIM-24A modules and two SM-X-64A modules cabled to the console ports of switches, firewalls and servers.
Where a regional office connects its call controller to a carrier SIP trunk, CUBE on the router handles the session border role, and an onboard PVDM4 supplies the DSP resources for transcoding and conferencing.
Product Comparison
|
Parameter |
ISR4351/K9 |
ISR4331/K9 | ||
|---|---|---|---|---|
|
Total onboard WAN or LAN 1G ports |
3 (3 RJ-45, 3 SFP, shared) |
3 |
4 (4 RJ-45, 4 SFP, shared) |
6 (4 RJ-45, 2 SFP) |
|
Aggregate throughput (default) |
200 Mbps |
100 Mbps |
1 Gbps |
Not published |
|
Aggregate throughput (performance license) |
400 Mbps |
300 Mbps |
2 Gbps |
Not published |
|
IPsec throughput (1400 bytes, autonomous mode) |
Not published |
Not published |
Not published |
Up to 1.9 Gbps |
|
Module slots |
3 NIM, 2 SM-X, 1 ISC |
2 NIM, 1 SM-X, 1 ISC |
3 NIM, 2 SM-X, 1 ISC |
2 NIM, 2 SM, 1 PIM |
|
DRAM |
4 GB (16 GB maximum) |
4 GB (16 GB maximum) |
2 GB data plane + 4 GB control plane |
8 GB |
|
Redundant power supply |
Not available |
Not available |
Internal AC, DC and PoE |
Dual PWR-CC1-650WAC 650W AC by default |
|
Default PoE budget |
0W |
0W |
0W |
0W |
|
PoE budget with PoE power supply |
500W |
250W |
500W redundant, 950W with PoE boost |
500W with PWR-CC1-1000WAC |
ISR4351/K9 carries three NIM slots, two SM-X slots and 200 Mbps of default throughput, against two NIM slots, one SM-X slot and 100 Mbps on ISR4331/K9. A site that stays at or below 300 Mbps, needs no more than two NIM slots and one SM-X slot, and draws no more than 250W of endpoint PoE fits ISR4331/K9. Above 400 Mbps, or where the router must run on two power supplies, ISR4451-X/K9 keeps the same slot layout and adds a fourth onboard port, 1 Gbps by default and 2 Gbps licensed. C8300-2N2S-6T trades the third NIM slot for a PIM slot and brings six onboard 1G ports, 8 GB of DRAM, dual 650W supplies and IPsec of up to 1.9 Gbps.
Ordering Checklist
- Technology package: The base router runs IP Base only; add SL-4350-SEC-K9 for IPsec and firewall, SL-4350-UC-K9 for voice and CUBE, or SL-4350-APP-K9 for MPLS and AVC. A missing package leaves those features unlicensed.
- HSEC license: Add FL-4350-HSEC-K9 when the design needs more than 1,000 secure tunnels or more than 250 Mbps of crypto bandwidth. It requires the security package and has no evaluation period.
- Performance license: Order FL-4350-PERF-K9 when the branch needs 400 Mbps of aggregate throughput. Without it the router stays at 200 Mbps.
- Memory and flash: MEM-4300-4GU8G or MEM-4300-4GU16G takes DRAM from 4 GB to 8 GB or 16 GB, and MEM-FLSH-4U16G takes flash from 4 GB to 16 GB.
- PoE power: Order PWR-4450-POE-AC when integrated switch modules must power endpoints, and PWR-GE-POE-4400 for PoE+ on the two onboard Gigabit ports. The two PoE sources are separate parts.
- DC input: Sites on -48 to -60 VDC need PWR-4450-DC in place of the AC supply, rated at up to 437W without PoE.
Optional Add-ons
|
Model |
Description |
|---|---|
|
PWR-4450-POE-AC |
1000W AC power supply with PoE module for the ISR 4350; up to 500W of endpoint PoE |
|
PWR-4450-DC |
DC power supply for the ISR 4450 and ISR 4350; -48 to -60 VDC, 437W |
|
PWR-GE-POE-4400 |
PoE module for the onboard Gigabit Ethernet ports of the ISR 4400 and ISR 4350 |
|
MEM-4300-4GU8G |
DRAM upgrade from 4 GB to 8 GB (4G+4G) for the ISR 4330 and ISR 4350 |
|
MEM-4300-4GU16G |
DRAM upgrade from 4 GB to 16 GB (8G+8G) for the ISR 4330 and ISR 4350 |
|
MEM-FLSH-4U16G |
eUSB flash upgrade from 4 GB to 16 GB for the ISR 4350 and ISR 4330 |
|
FL-4350-PERF-K9 |
Performance license raising aggregate throughput from 200 Mbps to 400 Mbps |
|
FL-4350-BOOST-K9 |
Boost performance license for CEF-only forwarding on the ISR 4350 |
|
FL-4350-HSEC-K9 |
HSEC export compliance license for the ISR 4350 |
|
SL-4350-SEC-K9 |
Security technology package license |
|
SL-4350-UC-K9 |
Unified Communications technology package license |
|
SL-4350-APP-K9 |
Application Experience technology package license |
|
64-channel voice DSP module for the onboard ISC slot | |
|
6-port dual-mode GE/SFP service module for an SM-X slot | |
|
24-port asynchronous serial NIM | |
|
ACS-4450-RM-23= |
23-inch rack kit for the ISR 4450 and ISR 4350 |
Front View
|
1 |
Power supply unit |
2 |
Router fan tray (hidden behind the removable bezel) |
|
3 |
LEDs |
4 |
Router power On/Off switch |
Rear View
|
1 |
Enhanced Service Module (SM-X) slot |
2 |
Enhanced Service Module (SM-X) slot |
|
3 |
Ground connection |
4 |
NIM slots |
|
5 |
GE management port |
6 |
USB Type A port |
|
7 |
USB Type B mini port |
8 |
Auxiliary port |
|
9 |
Console port |
10 |
RJ-45 port (GE 0/0/0, GE 0/0/1) |
|
11 |
SFP port (GE 0/0/0, GE 0/0/1, GE 0/0/2) |
12 |
RJ-45 port (GE/0/0/2) |
Specifications
| Parameter | Specification | Parameter | Specification |
|---|---|---|---|
| Product ID | ISR4351/K9 | Rack height | 2RU |
| Total onboard WAN or LAN 10/100/1000 ports | 3 | RJ-45-based ports | 3 |
| SFP-based ports | 3, each sharing a physical port with the same-numbered RJ-45 port | Total onboard WAN or LAN 10Gbps ports | 0 |
| RJ-45 port standards | 10BASE-T, 100BASE-TX, 1000BASE-T | SFP port modules | 1000BASE-LX/LH, SX, ZX, CWDM and 100 Mbps SFP modules |
| Management port | 1 dedicated Gigabit Ethernet port | NIM slots | 3 |
| Enhanced service-module slots | 2 | Double-wide service-module slots | 1, with no single-wide SM-X modules installed |
| Onboard ISC slot | 1, for PVDM4 voice DSP modules | OIR (all I/O modules) | Yes |
| Aggregate throughput (default) | 200 Mbps | Aggregate throughput (performance license) | 400 Mbps with FL-4350-PERF-K9 |
| Default memory DRAM | 4 GB | Maximum memory DRAM | 16 GB |
| Flash | 4 GB | Maximum flash memory | 16 GB |
| External USB 2.0 slots (type A) | 2 | USB console port (type B mini) | 1 |
| Serial console port (RJ-45) | 1 | Serial auxiliary port (RJ-45) | 1 |
| Power-supply options | Internal AC, DC and PoE | Redundant power supply | Not available |
| Default power supply model | PWR-4450-AC | Default power supply wattage | 450W AC |
| Default PoE budget | None; the default AC supply carries no endpoint PoE | PoE power supply | PWR-4450-POE-AC 1000W AC |
| AC input voltage | 100 to 240 VAC autoranging | AC input frequency | 47 to 63 Hz |
| AC input current range | 7.1 to 3.0 A | DC input voltage | -48 to -60 VDC |
| Typical power (no modules) | 48W | Maximum power with AC power supply | 430W |
| Maximum power with DC power supply | 437W (no PoE) | Maximum power with PoE power supply (platform only) | 990W |
| Maximum endpoint PoE power from PoE power supply | 500W | Front-panel PoE+ on onboard ports | GE 0/0/0 and GE 0/0/1, 802.3at, 30.8W total |
| Dimensions (H x W x D) | 3.5 x 17.25 x 18.5 in (88.9 x 438.15 x 469.9 mm) | Rack-mount 19 in. EIA | Included |
| Rack-mount 23 in. EIA | Optional | Wall-mount | Not supported |
| Weight with AC PS (no modules) | 13.1 kg (28.8 lb) | Weight with 1,000W PoE AC PS | 13.2 kg (29.0 lb) |
| Typical weight (fully loaded with modules) | 17.1 kg (37.7 lb) | Airflow | I/O side to bezel side |
| MTBF | 566,310 hours | Operating temperature | 0°C to 40°C (32°F to 104°F) |
| Storage temperature | -40°C to 70°C (-40°F to 158°F) | Relative humidity | 5% to 85% operating; 5% to 95% nonoperating |
| Operating altitude | 0 to 3,050 m (10,000 ft); 0 to 2,000 m (6,560 ft) in China | Sound pressure (typical/maximum) | 50.6/73.1 dBA |
| Sound power (typical/maximum) | 58.2/78.8 dBA | Safety certifications | UL 60950-1, CAN/CSA C22.2 No. 60950-1, EN 60950-1, AS/NZS 60950-1, IEC 60950-1 |
| EMC certifications | ICES-003 Class A, EN55032 Class A, CISPR32 Class A, AS/NZS CISPR 32 Class A, VCCI V-3, CNS 13438, EN 300-386, EN 55024, CISPR 24 | Software image | universalk9; autonomous and Catalyst SD-WAN controller mode from Cisco IOS XE 17.2.1 |
| Technology packages | IP Base by default; Security, Unified Communications and Application Experience by license | Crypto limits without HSEC | 1,000 secure tunnels and 250 Mbps of crypto bandwidth |
Get More Information
Need pricing, stock, or shipping details for the ISR4351/K9 ? Layer23-Switch can help you check current availability, lead time, and delivery options for this. Send us the part number, quantity, and destination country via live chat or email [email protected] for a fast quotation.
Quality Certifications
Customer Reviews
Questions & Answers
-
Which ROMMON release does ISR4351/K9 need for IOS XE 16.12 and for IOS XE 17.6?
-
Can ISR4351/K9 boot with only one DIMM installed?
-
What DC input range and maximum power does the DC supply for ISR4351/K9 have?
-
How many NIM-16A or NIM-24A modules can ISR4351/K9 hold?
-
Which fan assembly and rack kit PIDs are listed for ISR4351/K9?
Warranty
Layer23-Switch.com offers genuine, high-quality ICT products at competitive wholesale prices—ensuring exceptional value without compromising quality.
All items are brand new, original, and factory-sealed.
Upon request, each unit can be fully tested and verified by a Cisco CCIE-certified engineer to ensure perfect working condition before shipment.
Our Cisco CCIE-certified experts provide free professional support via phone, email, online chat, or remote login—helping you deploy and troubleshoot with confidence.
If you are not satisfied with your purchase, you may request an exchange or full refund. Our customer service team will guide you through the return process quickly and smoothly. Visit Return Policy page for more information.
We support multiple secure payment and logistics options, backed by industry-leading verification:
Visit How to Pay page for more information
Extended, Worry-Free Warranty Coverage Factory New Sealed Enterprise Hardware:
· 3 Years Factory New Sealed
Visit Warranty Policy page for more information
Verify, plan, and comparewith confidence
Use practical tools to check device details, review lifecyclemilestones, and compare hardware before you buy.
Standard Services
Personalized Service, Superior Product Maintenance for Ultimate Satisfaction.
- Projects and Technical Support
- Easy Purchasing Supply
- Product Lifecycle Protection
- Exclusive F3 Team Support
Customized Support for Your Needs with CCIE, HCIE, HPE ASE, etc.
Pre-sales support felt knowledgeable, not just transactional.
We had a post-purchase question. They connected us with the right resource.
Our internal vendor satisfaction survey gave Layer23 high marks.
Hope is not a strategy, good hardware is. This router is reliable.
3 GE ports and SM slots give us room to grow. Voice modules work perfectly.