Symmetric DSL broadband technology
FCC Form 477 technology code 20: 45,070 census-block deployment records nationwide. Filing volume and state reach are separate measurements.
Filing volume rank is not state-reach rank
Symmetric DSL ranks #9 of 10 FCC technology codes by census-block records, and #9 of 10 by number of states with at least one filing (42 states).
- #9
- of 10 tech codes by records
- 45,070
- total deployment records
- #9
- of 10 tech codes by state reach
- 42
- states with >=1 filing
Filing volume (records) and state reach (how many states report the technology at all) are different measurements - a technology can lead one and trail the other.
Symmetric DSL vs all FCC technology codes by filing volume
Where this technology's Form 477 record count sits among every technology code on PlainBroadband
45,070 9th of 10 higher than 1 of 10 technology codes
Technology codes, banded by nationwide deployment-record count
Each bar is a band; taller bars hold more technology codes. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source FCC Form 477 fixed broadband deployment · June 2020
Top states for Symmetric DSL by reported deployment records
FCC Form 477 fixed broadband deployment data (June 2020 status)
Montana leads Symmetric DSL filings with 9,246 records ; Washington is second at 8,779. Counts are provider-by-census-block filings for technology code 20, not subscriber totals.
About Symmetric DSL
Symmetric DSL (SDSL, HDSL) delivers equal upload and download speeds over copper lines. It is primarily a business-grade technology and is not typically marketed to residential customers.
Symmetric DSL filing-volume reading
Symmetric DSL opens on filing volume: #9 of 10 FCC technology codes by census-block records (45,070 filings). FCC technology code 20 is a copper / DSL family label in Form 477.
Symmetric DSL sits in the lower third of Form 477 technology codes by record volume (< 2,618,693). Thin filing books still matter when they concentrate in a few states or business-grade niches rather than mass residential footprints.
Montana alone accounts for 20.5% of Symmetric DSL filings (9,246 of 45,070), a concentrated book where one state can swing the national picture. Form 477 historically let providers mark a whole census block from a single reachable address; treat these counts as declared capability, not address-level availability, speed, or price.
Technologies near Symmetric DSL on Form 477 scale
Peer codes for Symmetric DSL by census-block record volume first, then state/territory reach (record floor ≥1,000, state floor ≥5).
Similar deployment-record volume
Nearest technology codes by total records (45,070 here).
Similar state/territory reach
Nearest codes by states with filings (42 here), excluding the record-volume set.
Read our methodology - how this data is sourced, computed, and verified.
What to do with Symmetric DSL filings
45,070 records is filing volume, not proof of active service at any one address.
- Compare Symmetric DSL against Other Copper, a similarly-filed technology, before drawing conclusions from volume alone. Compare to Other Copper
- See which states report the most Symmetric DSL filings and how coverage concentrates. Browse by state
- Find your own speed tier and what technology mix typically delivers it. Speed tier finder
Figures are FCC Form 477 fixed-deployment data as of June 2020, the final Form 477 release, self-reported by census block. For current, address-level availability, use the FCC National Broadband Map.
PlainBroadband is rendered directly from the FCC Form 477 fixed broadband deployment dataset (June 2020 status, the final Form 477 release), no number is typed in by an editor. This technology's coverage figures are computed directly from the underlying FCC Form 477 census-block records, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of June 2020.