By Dominic Sakwa, Technical Sales Expert

ISPs have to balance the demands of ever-increasing consumer bandwidth, strict operational budgets, and the requirement for rock-solid reliability, all while preserving cooling, power, and rack space. While loud, fan-cooled machines increase maintenance and data-hall cooling expenses, traditional switches frequently become bottlenecks as subscriber speeds rise to multi-gigabit levels. Remote sites add another layer of complexity, with limited power budgets, harsh environmental conditions, and the need for out‑of‑band management to avoid costly truck rolls.

The MikroTik CRS309‑1G‑8S+IN was designed from the ground up to address these challenges head‑on. With eight 10 Gbps SFP+ uplinks in a single, passively cooled chassis, it delivers carrier-grade throughput without the noise, heat, or moving parts that plague conventional switches. 

The broad voltage acceptance and PoE-powered management port of the MikroTik CRS309-1G-8S+IN simplify deployment in remote huts and towers, while dual-boot firmware lets you toggle between full-blown RouterOS services (BGP, MPLS, QoS) and a lean, wire-speed Layer 2 SwOS, giving ISPs unprecedented flexibility. In the following sections, we'll explore how each technical feature of the MikroTik CRS309‑1G‑8S+IN translates into tangible cost savings, operational agility, and future‑proof scalability for today's demanding ISP networks.

Key Features of the MikroTik CRS309-1G-8S+IN

1. Maximizing Throughput with Eight 10 Gbps SFP+ Ports

The MikroTik CRS309‑1G‑8S+IN offers eight SFP+ slots, each capable of 10 Gbps, delivering a total switching capacity of 162 Gbps and non‑blocking throughput of 81 Gbps.

Benefit for ISPs: Easily aggregate multiple high‑speed fiber feeds or peer connections without oversubscription. An 8×10 G uplink fabric lets you future‑proof your network as customer bandwidth demands grow.

2. Compact, Rugged Design with Passive Cooling

Encased in a sleek, all‑metal chassis that doubles as a heatsink, the MikroTik CRS309‑1G‑8S+IN is passively cooled—no fans, no moving parts, no dust buildup.

Benefit for ISPs: Zero audible noise in head‑end or POP rooms and minimal maintenance. The industrial‑grade enclosure is rated from –40 °C to +70 °C, ensuring reliable operation in harsh outdoor‑adjacent environments.

3. Dual‑Boot Flexibility: RouterOS or SwOS

With dual‑boot support, you can choose between MikroTik's powerful RouterOS (full routing, firewall, MPLS, BGP/OSPF, QoS) or the lightweight SwOS (switch‑only, wire‑speed layer‑2).

Benefit for ISPs: Tailor your control panel —deploy advanced layer‑3 services on aggregation nodes, or run a stripped‑down, ultra‑fast switch in distribution layers. Switching between OSes is seamless.

4. Powerful Hardware Core for Advanced Services

Under the hood sits a dual‑core 800 MHz CPU and 512 MB of RAM, backed by 16 MB of flash storage.

Benefit for ISPs: Run deep‑packet inspection, hot‑standby VRRP, traffic shaping, and per‑subscriber queues without becoming CPU‑bound. Large RAM supports extensive routing tables and dynamic session states.

5. Flexible Management and Remote Power

Management is via a dedicated 1 GbE port that also supports  802.3af/at PoE (or passive PoE). There's also an RS232 serial console for out‑of‑band access.

Benefit for ISPs: Power and manage the switch over a single fiber copper uplink—ideal for remote huts or towers. If network loops occur, serial access lets technicians recover units without a physical reboot.

6. Wide Voltage Range & Low Power Consumption

The MikroTik CRS309-1G-8S+IN accepts 12–57 V DC (via jack) or 18–57 V PoE, drawing just 17 W–23 W depending on module load.

Benefit for ISPs: Easily integrate into existing DC power plants or PoE-powered remote sites. Low power draw reduces OPEX and allows operation on smaller solar/battery setups.

7. Enterprise‑Grade Features at a Value Price

The MikroTik CRS309-1G-8S+IN comes with license level 5, unlocking full feature sets in RouterOS—including hotspot, VPN, MPLS, and advanced QoS. Rack‑mount ears and a grounding terminal are included.

Benefit for ISPs: All‑in‑one solution—no need to purchase extra feature licenses. Grounding provision ensures compliance in earthed installations. Rack‑ears simplify deployment in standard 19-inch cabinets.

Cut costs, not capacity!

For ISPs building out high‑capacity aggregation rings, peering points, or serving dense multi‑gigabit customers, the MikroTik CRS309‑1G‑8S+IN delivers unmatched port density, throughput, and operational flexibility in a rugged, low‑power package. Its blend of advanced software, carrier‑grade hardware, and cost‑effectiveness makes it the optimal choice for next‑generation service networks.

Contact us today for more information on the MikroTik CRS309-1G-8S+IN or to place your order.