# CGNAT Allocation Analysis

This report analyzes the CGNAT (100.64.x.x) subnet allocations across all network sites to identify which sites use /22 allocations versus other sizes.

## Summary

### Sites Using /22 Allocations
1. **Climax** - 100.64.4.0/22 (100.64.4.0 - 100.64.7.255)
2. **Culleoka** - 100.64.24.0/22 (100.64.24.0 - 100.64.27.255)
3. **Site 982** - 100.64.32.0/22 (100.64.32.0 - 100.64.35.255)
4. **New Hope** - 100.64.16.0/22 (100.64.16.0 - 100.64.19.255)
5. **Site 380** - 100.64.8.0/22 (100.64.8.0 - 100.64.11.255)

### Sites Using /20 Allocations
1. **Site 494** - 100.64.160.0/20 (100.64.160.0 - 100.64.175.255)
2. **Lowry Crossing** - 100.64.144.0/20 (100.64.144.0 - 100.64.159.255)

## Detailed Site Information

### /22 Allocations (1,024 addresses each)
| Site | CGNAT Subnet | Router IP | Interface |
|------|-------------|-----------|-----------|
| Climax | 100.64.4.0/22 | 100.64.7.254/22 | climax-bridge |
| Culleoka | 100.64.24.0/22 | 100.64.27.254/22 | ether2-netonix |
| Site 982 | 100.64.32.0/22 | 100.64.35.254/22 | 982 |
| New Hope | 100.64.16.0/22 | 100.64.19.254/22 | sfp-sfpplus1-edgepoint |
| Site 380 | 100.64.8.0/22 | 100.64.11.254/22 | combo1-380 |

### /20 Allocations (4,096 addresses each)
| Site | CGNAT Subnet | Router IP | Interface |
|------|-------------|-----------|-----------|
| Site 494 | 100.64.160.0/20 | 100.64.175.254/20 | 494 |
| Lowry Crossing | 100.64.144.0/20 | 100.64.159.254/20 | lowrycrossing |

## Key Observations

1. **Allocation Size Pattern**: 
   - 5 sites use /22 allocations (1,024 addresses)
   - 2 sites use /20 allocations (4,096 addresses)

2. **Larger Sites**: Sites 494 and Lowry Crossing have 4x larger CGNAT allocations compared to the other sites, suggesting they either serve more customers or were allocated larger blocks for future growth.

3. **Address Usage**: The /22 sites can support up to 1,022 customer connections (excluding network and broadcast addresses), while the /20 sites can support up to 4,094 customer connections.

4. **Sequential Allocation**: The /22 allocations appear to be somewhat sequential:
   - 100.64.4.0/22 (Climax)
   - 100.64.8.0/22 (Site 380)
   - 100.64.16.0/22 (New Hope)
   - 100.64.24.0/22 (Culleoka)
   - 100.64.32.0/22 (Site 982)

5. **Separate Range for /20s**: The /20 allocations are in a different part of the CGNAT space:
   - 100.64.144.0/20 (Lowry Crossing)
   - 100.64.160.0/20 (Site 494)