Category: Technology

Recently, I needed to figure out how many 2D rectangles in different quantities I could fit in one large rectangle. (I actually needed to know how many 12″x12″, 10″x10″, 8″x8″, and 13″x8″ shooting targets I could cut out of a sheet of steel that is 315″x78″ in size while minimizing any leftover space.) I came across an algorithm online and modified it a bit to make it a easier to use and understand. Check it out at the link below.

2D Bin Packing Calculator

It turns out, I can get 97% utilization with the following sizes and quantities.

Many devices are connected to each other over different cables and interfaces. But not all devices can transfer data at the same speeds. The device or connection with the lowest speed determines the maximum speed. Following are some common devices and their speeds.

 Cell Phone Interfaces

• Edge (Evolution type 2 MS): 148 kB/s download
• HSPA+: 5.25 MB/s download
• LTE (2×2 MIMO): 21.6 MB/s
• LTE (4×4 MIMO): 40.75 MB/s download

Wide Area Networks

• DS1 / T1: 0.2 MB/s

Local Area Networks

• Ethernet 10BASE-T: 1.25 MB/s
• Fast Ethernet 100BASE-TX: 12.5 MB/s
• FireWire 400: 50 MB/s
• Gigabit Ethernet 1000BASE-T: 125MB/s

Wireless Networks

• IEEE 802.11a: 6.75 MB/s
• IEEE 802.11b: 1.375 MB/s
• IEEE 802.11g: 6.75 MB/s
• IEEE 802.11n: 75 MB/s

Wireless Personal Area Networks

• Bluetooth 4.0: 3 MB/s

Peripheral

• USB low speed: 192 kB/s
• USB full speed: 1.5 MB/s
• USB hi-speed (USB 2.0): 60 MB/s
• USB super speed (USB 3.0): 625 MB/s x 2
• Thunderbolt: 1,250 MB/s x 2

View a complete list of device speeds