WAN Optimization
Estimate effective WAN throughput gains from compression, caching and deduplication.
About WAN Optimization
WAN optimization appliances increase the effective, perceived throughput of a fixed physical link by reducing how much data actually needs to cross it — deduplication avoids re-sending data blocks the remote end already has cached, and compression shrinks the data that must be sent. These two techniques stack multiplicatively: a link that only physically carries the actual bandwidth can behave, from an application's perspective, as if it carries dedup_ratio × compression_ratio times that bandwidth for suitable (compressible, redundant) traffic patterns.
Formula
Effective bandwidth
effective_bw = actual_bw × dedup_ratio × compression_ratio
Worked example
With the default values below, WAN Optimization returns Effective Bandwidth (perceived throughput) of 150.0. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Actual Link Bandwidthminimum 0.1 Mbps
- 50 Mbps
- Deduplication Ratiominimum 1
- 1.5
- Compression Ratiominimum 1
- 2
Results
- Effective Bandwidth (perceived throughput)
- 150.0 Mbps
- Combined Optimization Ratio
- 3.00
- Effective Bandwidth Gain
- 200.0%
Step by step
- 1Values used
- 2Effective bandwidth
- 3Effective Bandwidth (perceived throughput)= 150.0 Mbps
- 4Combined Optimization Ratio= 3.00
- 5Effective Bandwidth Gain= 200.0
Assumptions and limits
- The result is derived only from the 3 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
- Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
Does WAN optimization increase the physical link speed?
No — the underlying physical bandwidth is unchanged. WAN optimization reduces the volume of data that must actually cross the link for a given amount of useful data delivered, which produces the same practical effect as a faster link for compatible traffic, but doesn't help traffic types that don't compress or deduplicate well (e.g. already-compressed video, encrypted traffic).
Why do dedup and compression ratios vary so much by traffic type?
Deduplication benefits most from repetitive data patterns — file shares, backups, and VDI traffic often see high dedup ratios because similar blocks recur across transfers. Compression benefits most from data with statistical redundancy — text, logs, and uncompressed formats compress well, while already-compressed or encrypted data barely compresses further, sometimes even growing slightly.
What traffic doesn't benefit much from WAN optimization?
Encrypted traffic (VPN tunnels, TLS/HTTPS, already-encrypted backups) looks like random noise to both deduplication and compression algorithms, so it typically sees minimal benefit unless the WAN optimizer can inspect it before encryption or the endpoints support optimization-aware encryption.