The LGS552P can be configured from a web gui or from the command line via a console port or telnet. The menus on the LGS552P are easy to figure out. They remind me of the menus on Cisco's small business SG switches, such as the SG500-28P I reviewed awhile back. Interestingly, they both share a slight menu lag with the same "Processing Data" pop-up window (shown below) when a configuration is being applied.
Below is a summary of the LGS552P menus, which provides an overview of configuration options. The headers in the below list are the main menus and bulleted items are sub-menus. Note, some of the sub-menus have additional menus.
An important aspect to configuring the LGS552P is you need to save your configurations after they've been applied, or you'll lose them in a power cycle. You'll find the option to save your configurations in the LGS552P's maintenance menu.
One thing I would like to see on the 52-port LGS552P is an efficient method to configure multiple ports simultaneously. As it stands, you can use the VLAN Membership menu to click and change VLAN assignments to ports relatively easily. But it would be nice to have a range function to apply changes to a range of ports at the same time.
The LGS552P can provide up to 375 watts of power to PoE-capable devices on ports 1-48. I successfully powered multiple PoE devices to the LGS552P, including a Ubiquiti Access Point, Grandstream VoIP device and a NETGEAR M4100 switch. As you can see below, the LGS552P reports those three devices are drawing a total of 21800 milli-Watts, or 21.8 Watts.
Power over Ethernet
The LGS552P supports a maximum of 30 W per port. Of course, if all ports drew 30 W, that would exceed the switch's PoE capacity. So the LGS552P has configuration options to limit power by port, PoE class or priority. My three devices are drawing an average of 7.27 W each. 7.27 W to 48 ports totals 350 W, which is within the LGS552P's power budget of 375 W.
Power consumption on the LGS552P can be reduced with its Green Ethernet options. Options include 802.3 EEE (Energy Efficient Ethernet), which reduces power when there is no traffic on an interface, Energy-Detect mode, which reduces power when an interface is down, and Short-Reach mode, which reduces power on cables with a detected length of less than 50m. The interface LEDs can also be disabled to further reduce power consumption.
A basic switch operates at OSI Layer 2. That means it forwards data by examining source and destination MAC addresses. Switches forward data via hardware, allowing them to pass traffic at line rate. Line rate references the speed of the ports, which in this case is Gigabit speed. (The LGS552P also has two 10 Gigabit ports!) However, if data has to go from one VLAN to another, a Layer 2 switch typically sends the traffic to a router. Small network routers often route data packets with software, which is slower than hardware.
A Layer 3 switch can forward data based on MAC addresses at line rate, plus it can route data based on IP addresses (Layer 3) at line rate. Thus, a Layer 3 switch can improve performance in a network with multiple VLANs using different IP ranges because it can route data from one VLAN to another without sending the traffic to a router. It's important to note that even with a Layer 3 switch, you still need a router for software based functions like Network Address Translations (NAT.)
To use Layer 3 functions on the LGS552P, you need to enable Layer 3 mode, as shown in the screenshot below. This erases all previously configured settings, so you need to do this first if you plan to use Layer 3 routing. Layer 2 functionality is still available after Layer 3 mode is enabled, so you don't lose anything by enabling Layer 3 mode, as long as your connections and configurations are correct.
Layer 3 Mode
The LGS552P has basic Layer 3 functionality. You can assign an IP address to each VLAN in the switch, which enables it to automatically route traffic between those VLANs. You can also enter up to 64 static routes for routing traffic to other Layer 3 devices. The LGS552P also supports MAC and IP based Access Control Lists for filtering traffic between VLANs and/or to/from other Layer 3 devices. The LGS552P doesn't provide a DHCP server or support dynamic routing protocols like RIP or OSPF.
The screenshot below shows both the IPv4 route table and the IPv4 VLAN interface table. (The LGS552P also supports IPv6.) As you can see, the LGS552P has a static default route pointing to my router at 172.23.1.1, plus it has directly connected routes to 172.23.1.0 and 192.168.1.0. Those connected routes were automatically created by assigning IP address to each VLAN on the switch, which creates a VLAN interface.
I tested routing on the LGS552P with a PC connected to each VLAN. I gave each PC the LGS552P's VLAN interface as their gateway. I was able to successfully ping the Internet and ping devices on other VLANs. A traceroute confirmed the LGS552P was routing packets as intended.