Bits, Frames, and Packets

Bits, Frames, and Packets

Let's take a little overview of network equipment. At the bottom of the network food chain, you get the repeater. It does nothing but takes the bits, boost their signal, and send them on their way. Repeaters were the standard way to get around the 100 meter limit for cable. Just above that is the hub, similar to a repeater, and just as dumb, it generally just has lots of ports. Hubs don't do anything to segregate data and threats all the computers attached to it as a single broadcast domain. That is a hub forwards all packets to all ports and leaves it up to the nodes to decide if the packet was for them. Not the most efficient way to network, but it works well for smaller networks. Second from the top is the switch, which is what the ECS 2512FP is. Switches treat each port as an individual broadcast domain, sending data (frames) only to the port that needs it, thus enhancing speed and efficiency. This level of intelligence requires that a switch have some buffer memory and have a little processing be done with each packet that goes in and out. At the top of the network, food-chain is the router. Routers can contain switches. It is the big daddy and uber guru of networks, as it works with the highest level of intelligence, by protocol. Switches are generally a good upgrade if you have lots of hubs and want to extend the life of your network and kick up the speed.

We started at 100 Mbit/s

My initial encounters with a full Gigabit network remain vivid in my memory. I updated our home network to gigabit speed coming from 100 Mbit roughly 15 years ago, and truly appreciated the increased transfer speeds. The fact however is that gigabit has been around for a long time, too long even;  and throughout that period, storage speeds and requirements, as well as connectivity, have exploded in contrast to previous generations. For instance, gigabit is 125 MB/s, even a slow 5400 RPM hard disk these days can deliver 150 MB/s. With NVMe we now can copy in excess of 3GB/sec to even 7 GB/sec, yet over ethernet we remain limited. 

Gigabit, for the 99.99% out there is the fastest available connection. And hey, if you are only using your computer and the internet, this is completely OK because your internet connection is still the only limitation you have. However, if you are moving files over your network, particularly to numerous PCs, a 1G or gigabit network is a notable slowdown, and with Intel and AMD now integrating 2.5G network cards in their Z590/Z690 and AMD 500 series chipsets, faster network speeds are becoming a possibility for an increasing number of users. Today I'm taking a look at the EnGenius ECS2512FP, which supports 2.5G with POE and has the capability of supporting SFP+ transceivers for 10G, as well as other features.

Port Standards	802.3 10Base-T Ethernet 802.3u 100Base-TX Ethernet 802.3ab 1000Base-T Ethernet 802.3bz 2500Base-T Ethernet 802.3x Full-Duplex Flow Control
Network Ports	8 10/100/1000/2500 Mbps Ports + 4x SFP+ Ports
Switching Capacity	120 Gbps
SDRAM	512 MB
Flash Memory	128 MB
PoE++ Capable Ports	1-8 (802.3 af/at/bt)
Total PoE Budget	240W
Power Source	100 ~ 240VAC, 50-60Hz
LED Indicators	Power LED Fault LED PoE Max LED LAN Mode LED PoE Mode LED
Ports	Link/Activity/Speed (per Ethernet port) Link/Activity/Speed (per SFP slot)
L3 Features
Multiple IP Interface	20 IPv6 address
ARP Table	Max. 192 ARP entries
Static ARP	Static 192 ARP entries
IPv4 Static Route	Max. 63 entries
IPv6 Static Route	Max. 21 entries
L2 Features
MAC Address Table	16K
Jumbo Frame	9K
Multicast Group	Max 256 groups
MLD Snooping	MLD Snooping: v1
QoS-Number of Priority Queues Supported	Queue 8
Trust Mode	Cos/802.1p DSCP CoS/802.1p-DSCP
Scheduling Mechanism	Strict / WRR/ Strict + WRR
Bandwidth Control	Port-based bandwidth control (Ingress/Egress)
Port Security	Max. 256 Entries
Access Control List (ACL)	MAC Based ACL IPv4/IPv6 Based ACL ACL Binding Time base ACL
Web Interface(GUI)	HTTP IPv4 / IPv6 HTTPS IPv4 / IPv6
SSL Certificate	Certificate/Key Import
SNMP	SNMP v1/v2c/v3 Support
RMON	RMON 1,2,3,9
System Time	Time Setting/Daylight saving
Common L2 Features	802.1d Spanning tree Loopback Detection Multicast Filtering IGMP Multicast Forwarding IGMP Snooping MLD Multicast Forwarding 802.1Q VLAN tagging 802.3x flow control 802.3ad Link Aggregation IPv4 DHCP Relay IPv4 DHCP Snooping IPv4 DHCP Snooping Source MAC Address Check-up ARP Inspection ARP Packet Validation (additional validation checks) Voice VLAN Port-based VLAN Protocol-Based VLAN CoS Mapping 802. 1X Radius Authentication Protocol IPv4 Settings IPv6 Settings IEEE 802. 3az Energy Efficient Ethernet (EEE) Command Line Interface (CLI) SSH Server Telnet Server TFTP Client Configuration Upgrade/Backup Simple Network Time Protocol (SNTP) SYSLOG 802.1d Spanning tree
Environmental & Physical
Temperature Range	Operating: 32°F to 122°F (0°C to 50°C)
Humidity (Non-Condensing)	Operating: 5% - 95%
Package Contents	1x Cloud Managed Multi-Gig PoE++ Switch 1x Quick Installation Guide 1x Power Cord 1x RJ45 Console Cable 1x Rack Mount Kit
ECS2512FP Device	Weight: 5.7 lbs (2.6 kg) Width: 9.05? (230 mm) Length: 12.99? (330 mm) Height: 1.73? (44 mm)
Warranty	2 years

The EnGenius ECS2512FP thus has 8 full-duplex 10/100/1000/2500 ports for its connections, so you need to double that up. Most switch crossbars (the backplane) run in the gigahertz range, 120 Gbps for this one. But it is surprising to see that Engenius isn't compromising on speed for the sake of costs. A lot of crossbar bandwidth certainly does work out to the full-duplex 5000 Mbps for each port (2.5G each way).