Dell Networking S3148P PoE+ Switch

The Dell Networking S3148P is a 1RU managed campus access switch with 48 auto-sensing 10/100/1000Mb RJ45 ports delivering IEEE 802.3at PoE+ at up to 30.8W per port, two dedicated 10Gb SFP+ uplinks, two GbE combo media ports and a hot-swap expansion bay, running Dell Networking OS9.

Where it belongs in a network

The S3148P is the high-density PoE+ access switch of the family: forty-eight ports of IEEE 802.3at at up to 30.8W each in a single rack unit. That is enough to power an entire floor of wireless access points and IP handsets, or a full camera run, from one switch and one pair of power cords - no injectors, no midspans, no local outlets at the device.

It is also a full Layer 3 switch, which matters more in a PoE deployment than in a copper one. Cameras, access control and building systems usually want their own VLANs and their own routing policy, and OS9 gives you 511 VRF-lite instances, policy-based routing and Routed Port Monitoring to keep those domains separate and observable without adding a distribution-layer hop or a dedicated network tap.

Forty-eight gigabit access ports against 20Gbps of dedicated 10Gb SFP+ uplink is a 2.4:1 oversubscription ratio - fine for a PoE edge dominated by access points and handsets. Add the two-port 10GbE expansion module for 40Gbps of uplink and a 1.2:1 ratio if the switch is also carrying camera recording traffic to a central NVR.

PoE+ power planning

Each port delivers up to 30.8W under IEEE 802.3at. The switch ships with a single 1100W hot-swappable supply - and note that the 1100W part requires a C15 plug, not the C13 used by the non-PoE models, so the power cord is not interchangeable with an S3124 or S3148. Maximum system power consumption is 2,145W and maximum thermal output is 7,319.04 BTU/hr.

Put those two numbers side by side and the design intent is obvious: 2,145W of maximum draw against 1,100W per supply means a fully loaded S3148P needs both power supplies installed. The second supply is not only redundancy on this model - it is capacity. Order it with two supplies if you intend to run anything close to a full PoE+ load, and treat a single-supply S3148P as a partially-populated switch.

The thermal figure deserves the same attention. The non-PoE S3148 emits 221.11 BTU/hr; the S3148P at full load emits 7,319.04 BTU/hr, roughly thirty-three times more. Dell does not publish a single system PoE budget figure for this model, so we do not quote one - size from the per-port draw of your actual powered devices against installed supply wattage, and check the closet's cooling before you commit.

Stacking and the expansion bay

Two dedicated stacking ports sit on the rear of the chassis, each rated at 21Gbps, giving 84Gbps of full-duplex stacking bandwidth. Up to twelve switches join a single stack, managed under one IP address, for a maximum of 624 ports presented as one logical device. Stacking cables are available in 0.25m, 1m and 3m, which is enough to reach across a rack or between two adjacent racks but not across a room - plan stack members physically together.

Because the stacking ports are separate from the front-panel SFP+ ports, stacking costs you no uplink capacity. That is a real architectural difference from switches that stack over their uplinks, and it is the reason the family scales cleanly: a twelve-unit stack still has twenty-four dedicated 10Gb SFP+ uplinks available to the core.

The single hot-swap expansion bay accepts either a two-port 10GBASE-T RJ45 module or a two-port 10GbE SFP+ module. Choose 10GBASE-T when the uplink is short structured copper and you want to avoid optics entirely; choose SFP+ when the uplink is fiber, when you need a DAC to a top-of-rack switch, or when you want the lower per-port power draw of a passive twinax run.

Operating system and management

Every S3100 ships with Dell Networking OS9 - the same image and the same command language used across the Dell S-series and N-series of the period, so a team already running OS9 elsewhere does not learn a second CLI. Management is by CLI over console, Telnet or SSHv2, by SNMP v1/v2c/v3 including Dell OpenManage Network Manager, and by a dedicated out-of-band 10/100/1000BASE-T management port that is entirely separate from the data plane. A USB Type-A port on the front takes configuration from a flash drive, and the switch carries dual firmware images on-board so an upgrade can be rolled back without a console session.

The feature set is genuinely enterprise-grade rather than a cut-down campus stack. Layer 3 includes OSPFv2 and OSPFv3, BGP-4 with IPv6 multiprotocol extensions, IS-IS, RIP, VRRP, PIM-SM and IGMPv1/v2/v3, with 16K IPv4 and 8K IPv6 routes and 511 VRF-lite instances for tenant or zone isolation. VLT provides active-active dual-homing without spanning-tree blocking. Interoperability with Cisco PVST+ is built in, which matters when the switch is going into a mixed-vendor campus. Security covers 802.1X with RADIUS, MAC Authentication Bypass, tiered authentication so one port can accept several methods in priority order, TACACS+ accounting and FIPS 140-2 approved cryptography. sFlow v5 and Routed Port Monitoring give you visibility across a Layer 3 domain without dedicated taps, and OpenFlow 1.3 is available for SDN deployments.

Where this model sits in the S3100 series

All five S3100 switches share the same 1RU chassis, the same Dell Networking OS9 image, the same stacking architecture and the same expansion bay. They differ in three things only: port count, port media, and whether the copper ports deliver PoE+.

• Dell Networking S3124
• Dell Networking S3124F
• Dell Networking S3124P
• Dell Networking S3148
• S3148P (this page)

A factory-sealed, new-in-box S3148P is also available - see Dell Networking S3148P (New Sealed) - and the open-networking alternative in this port class is the Dell Networking S3048-ON, which runs ONIE rather than OS9.

Condition, testing and support

Every unit is professionally refurbished: inspected, cleaned, configuration-wiped, firmware-checked and functionally tested on every port before it ships, and it ships with warranty. Refurbished S3100-series hardware is the sensible way to buy this generation - the platform is mature, the OS9 feature set is stable and fully documented, and the secondary market is where the supply now is.

Power supplies, expansion modules, stacking cables, rail kits and optics are configurable above. If you need a specific optic mix, a particular PoE supply configuration or a quantity for a multi-closet rollout, request a quote and we will build it to your bill of materials.