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Infinity Fabric

Infinity Fabric, the successor to AMD HyperTransport, is a high speed interlink used for data exchange between the CPU, PCIe, I/O, and memory. Infinity Fabric is also used for intra-die data communications as well, linking together multiple CCX (CPU Complexes) within the AMD Ryzen, Threadripper, and Epyc CPUs.

AMD’s Infinity Fabric design consists of two distinct parts: Scalable Control Fabric (SCF) and Scalable Data Fabric (SDF). The SCF includes power management, security, and anything involving maintaining the operation of the chip while the SDF is what ties the memory and the compute components together. As such, the latency of the SDF must be low enough to minimize effects of the inter-die data exchange, and it must be designed to be scalable to support multiple dies. AMD claims that the SDF can perfectly scale up to 64 cores.

IOPS

IOPS, or Input/Output Operations per Second, is a storage performance metric which measures how many reads and writes are occurring every second. As smaller files take less time to transfer compared to larger files, the IOPS metric is typically used to measure transfers of 4K or 8K file sizes. Larger filesize reads and writes such as 128K, 512K and larger are typically measured by throughput such as MB/s (Megabytes Per Second) or GB/s (Gigabytes Per Second).

IPv6

IPv6, or Internet Protocol Version 6, is the next generation of Internet Protocol and is designed to replace the aging IPv4, or Internet Protocol Version 4.

 

Why do we need IPv6?

In order to understand why we need IPv6, we need to quickly understand IPv4 and its limitations.

In the early days of the internet, in order for computers and other devices to communicate, the US Government funded ARPANET, or Advanced Research Projects Agency Network, adopted a new standard called IPv4. This protocol governed how traffic moved around the internet at the time and continues to be in use today.

However, IPv4 has a major limitation. As it uses 32-bit addresses, it’s limited to 232 addresses which means there’s a maximum of just 4,294,967,296, or about 4 Billion addresses. Subtracting private networks along with multicast addresses and you’re left with a lot less. While this may not have been a problem back in 1983 when IPv4 was adopted by ARPANET, with the rise of personal computing, mobile computing, and IoT, we’re quickly running out of addresses.

To solve this issue, IPv6 was invented by the IETF, or Internet Engineering Task Force. Unlike IPv6 which uses just 32-bit addresses, IPv6 uses 128-bit addresses raising the total amount of IP addresses from roughly 4.3 Billion to 3.4 x 1038 , or 340 undecillion (trillion trillion) addresses.

 

What do IPv6 addresses look like?

IPv4

If you’ve ever used the internet, you’re probably very familiar with the IPv4 address. The address is simply four groups of three digits separated by periods.

The following are examples IPv4 addresses:

  • 10.10.10.10
  • 192.168.1.1
  • 256.256.256.256

IPv6

IPv6 addresses are quite different compared to IPv4 addresses. Due to its 128-bit addressing, IPv6 uses eight groups of four alphanumeric characters separated by colons. Any groups of zeros can be written as simply a single zero or can be omitted altogether.

The following are examples of the same IPv6 address:

  • 2620:2761:abcd:0000:0000:0000:2126:3462
  • 2620:2761:abcd:0:0:0:2126:3462
  • 2620:2761:abcd::2126:3462