diff --git a/NewMutableEncodingDesign.md b/NewMutableEncodingDesign.md
index 83d0264..3752359 100644
--- a/NewMutableEncodingDesign.md
+++ b/NewMutableEncodingDesign.md
@@ -60,33 +60,33 @@ relative to using a hash truncated to K+T bits.
 A likely security parameter K (=kappa) would be 96, 128, or 160 bits.
 [96 bits is too short IMHO --David-Sarah]
 
-Assuming a `tahoe:` prefix and no additional metadata, here's what
+Assuming a `lafs:` prefix and no additional metadata, here's what
 various lengths of base62-encoded filecaps would look like:
 
  * 1*K:
-  * 96 `tahoe:14efs6T5YNim0vDVV`
-  * 128 `tahoe:4V2uIYVX0PcHu9fQrJ3GSH`
-  * 160 `tahoe:8gdR7Epld72UvkF6Pe9hhT8NQx3`
+  * 96 `lafs:14efs6T5YNim0vDVV`
+  * 128 `lafs:4V2uIYVX0PcHu9fQrJ3GSH`
+  * 160 `lafs:8gdR7Epld72UvkF6Pe9hhT8NQx3`
  * 2*K:
-  * 192 `tahoe:072Og6e75IOP9ZZsbR1Twjs6X5xXJnBAF`
-  * 256 `tahoe:fZeioazoWrO62reiAjzUAyV0uz3ssh6Hnanv8cKMClY`
-  * 320 `tahoe:j6Re0BbWp7DqJtgd9fUXl4pWiD5kr1mjT9DtudJ72o0vhPen83Utza`
+  * 192 `lafs:072Og6e75IOP9ZZsbR1Twjs6X5xXJnBAF`
+  * 256 `lafs:fZeioazoWrO62reiAjzUAyV0uz3ssh6Hnanv8cKMClY`
+  * 320 `lafs:j6Re0BbWp7DqJtgd9fUXl4pWiD5kr1mjT9DtudJ72o0vhPen83Utza`
  * 3*K:
-  * 288 `tahoe:11DriaxD9nipA10ueBvv5uoMoehvxgPerpQiXyvMPeiUUdtf6`
-  * 384 `tahoe:3a31SqUbf8fpWE1opRCT3coDhRqTU7bDU2AvC3RQJBu6ZNFhVscyxA9slYtPVT79x`
-  * 480 `tahoe:P6rGeI6CwlG4i8W2l6haSoC9rfPjw0KHBi8xAk4F8vdhnRhL8nwE27CitJ9Rld06HuKt8VucypJRcbGFo`
+  * 288 `lafs:11DriaxD9nipA10ueBvv5uoMoehvxgPerpQiXyvMPeiUUdtf6`
+  * 384 `lafs:3a31SqUbf8fpWE1opRCT3coDhRqTU7bDU2AvC3RQJBu6ZNFhVscyxA9slYtPVT79x`
+  * 480 `lafs:P6rGeI6CwlG4i8W2l6haSoC9rfPjw0KHBi8xAk4F8vdhnRhL8nwE27CitJ9Rld06HuKt8VucypJRcbGFo`
 
 Adding 2 metadata characters and a clear separator gives us:
 
- * 96: `tahoe:MW-14efs6T5YNim0vDVV`
- * 128: `tahoe:DW-4V2uIYVX0PcHu9fQrJ3GSH`
- * 160: `tahoe:DW-8gdR7Epld72UvkF6Pe9hhT8NQx3`
- * 192: `tahoe:MR-072Og6e75IOP9ZZsbR1Twjs6X5xXJnBAF`
- * 256: `tahoe:DR-fZeioazoWrO62reiAjzUAyV0uz3ssh6Hnanv8cKMClY`
- * 288: `tahoe:MV-11DriaxD9nipA10ueBvv5uoMoehvxgPerpQiXyvMPeiUUdtf6`
- * 320: `tahoe:MR-j6Re0BbWp7DqJtgd9fUXl4pWiD5kr1mjT9DtudJ72o0vhPen83Utza`
- * 384: `tahoe:DV-3a31SqUbf8fpWE1opRCT3coDhRqTU7bDU2AvC3RQJBu6ZNFhVscyxA9slYtPVT79x`
- * 480: `tahoe:MV-P6rGeI6CwlG4i8W2l6haSoC9rfPjw0KHBi8xAk4F8vdhnRhL8nwE27CitJ9Rld06HuKt8VucypJRcbGFo`
+ * 96: `lafs:MW-14efs6T5YNim0vDVV`
+ * 128: `lafs:DW-4V2uIYVX0PcHu9fQrJ3GSH`
+ * 160: `lafs:DW-8gdR7Epld72UvkF6Pe9hhT8NQx3`
+ * 192: `lafs:MR-072Og6e75IOP9ZZsbR1Twjs6X5xXJnBAF`
+ * 256: `lafs:DR-fZeioazoWrO62reiAjzUAyV0uz3ssh6Hnanv8cKMClY`
+ * 288: `lafs:MV-11DriaxD9nipA10ueBvv5uoMoehvxgPerpQiXyvMPeiUUdtf6`
+ * 320: `lafs:MR-j6Re0BbWp7DqJtgd9fUXl4pWiD5kr1mjT9DtudJ72o0vhPen83Utza`
+ * 384: `lafs:DV-3a31SqUbf8fpWE1opRCT3coDhRqTU7bDU2AvC3RQJBu6ZNFhVscyxA9slYtPVT79x`
+ * 480: `lafs:MV-P6rGeI6CwlG4i8W2l6haSoC9rfPjw0KHBi8xAk4F8vdhnRhL8nwE27CitJ9Rld06HuKt8VucypJRcbGFo`
 
 [#217:c44](http://allmydata.org/trac/tahoe/ticket/217#comment:44) says that,
 if we don't need to prevent collisions, then we can use a K-bit hash for