More detailsNeighboring subnets, expanded address, reverse DNS, and hextet breakdown
Neighboring /117 subnets
- Expanded address
- Compressed address
- Network (expanded)
- Last address (expanded)
- Prefix mask
- Total addresses (exact)
- Reverse DNS (PTR)
- Host bits / network bits
Hextet breakdown
20010db8abcd00120000000000000001
NetworkSplit groupHost
Quick facts for IPv6 /117
- Prefix mask: ffff:ffff:ffff:ffff:ffff:ffff:ffff:f800
- Total addresses: 2¹¹
- Approx. count: 2,048
- /64 subnets: —
IPv6 /117 reference guideBit split, overview, key facts, sizing tables, design notes, standards, and FAQ
Network / host bit split
netnetnetnetnetnetnetmix
Network bits (117)Split hextetHost bits (11)
- Network bits
- 117
- Host bits
- 11
- Prefix mask
- ffff:ffff:ffff:ffff:ffff:ffff:ffff:f800
- Total addresses
- 2¹¹
- Approx. count
- 2,048
- /64 subnets
- —
- Addresses formula
- 2^11
- /64 relationship
- smaller than a /64
Overview
A /117 contains 2¹¹ addresses (2,048), suitable for small VLANs, management subnets, or lab scenarios. Standard production LANs should still use /64; this size is for deliberate constraints.
Common use cases
- Small management VLANs
- Test and staging environments
- Subnetting practice for certification exams
Key facts
- A /117 fixes 117 network bits and leaves 11 host bits — 2¹¹ total addresses.
- In network design terms, /117 is typically a constrained management or lab segment.
- Written out, /117 holds exactly 2,048 addresses.
- A /117 is 1/2⁵³ of a standard /64 LAN subnet.
Design guidance
A /117 can work for small management VLANs, out-of-band networks, or certification lab exercises where you deliberately cap the host count. For router interconnects, prefer /127 (RFC 6164) over /117. For ordinary LANs, stay with /64 regardless of how small the segment feels.
Practical example
In a lab, 2001:db8:abcd:0012::1/117 might number a small segment with 2,048 addresses. In production, you would normally expand this to a full /64 unless you have a documented exception.
Prefix sizing reference
Frequently asked questions
Common questions about IPv6 /117 blocks, prefix sizes, and use cases.