From 1ae70bae19212489407d10e1878d27191182b93d Mon Sep 17 00:00:00 2001 From: ianswett Date: Thu, 13 Aug 2020 16:39:07 -0400 Subject: [PATCH 1/3] Update initial congestion window on MTU decrease Fixes #3997 by specifying that IW should be updated if the max packet size decreases in order to complete the handshake. --- draft-ietf-quic-recovery.md | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/draft-ietf-quic-recovery.md b/draft-ietf-quic-recovery.md index 0c7dfebd4d..e5c1ef9323 100644 --- a/draft-ietf-quic-recovery.md +++ b/draft-ietf-quic-recovery.md @@ -751,6 +751,11 @@ twice the maximum datagram size. This follows the analysis and recommendations in {{?RFC6928}}, increasing the byte limit to account for the smaller 8 byte overhead of UDP compared to the 20 byte overhead for TCP. +If the maximum datagram size is decreased in order to complete the handshake, +the initial congestion window SHOULD be recalculated with the new smaller size. +This avoids overly large initial congestion windows. The initial window is +not recalculated at any other time. + Prior to validating the client's address, the server can be further limited by the anti-amplification limit as specified in Section 8.1 of {{QUIC-TRANSPORT}}. Though the anti-amplification limit can prevent the congestion window from From b01abe68367e571b6593ebb02fcd91cf674130d5 Mon Sep 17 00:00:00 2001 From: ianswett Date: Sat, 15 Aug 2020 20:34:57 -0400 Subject: [PATCH 2/3] Update draft-ietf-quic-recovery.md --- draft-ietf-quic-recovery.md | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/draft-ietf-quic-recovery.md b/draft-ietf-quic-recovery.md index e5c1ef9323..a93ddf4514 100644 --- a/draft-ietf-quic-recovery.md +++ b/draft-ietf-quic-recovery.md @@ -752,9 +752,10 @@ in {{?RFC6928}}, increasing the byte limit to account for the smaller 8 byte overhead of UDP compared to the 20 byte overhead for TCP. If the maximum datagram size is decreased in order to complete the handshake, -the initial congestion window SHOULD be recalculated with the new smaller size. -This avoids overly large initial congestion windows. The initial window is -not recalculated at any other time. +the initial congestion window SHOULD be recalculated with the new smaller size +and the congestion window SHOULD be set to the smaller initial congestion +window. This avoids overly large initial congestion windows. The initial +window is not recalculated at any other time. Prior to validating the client's address, the server can be further limited by the anti-amplification limit as specified in Section 8.1 of {{QUIC-TRANSPORT}}. From 5af85b5602b9562d13e2b94933eebdf4b9f6bf62 Mon Sep 17 00:00:00 2001 From: ianswett Date: Tue, 18 Aug 2020 18:16:11 -0400 Subject: [PATCH 3/3] Update draft-ietf-quic-recovery.md --- draft-ietf-quic-recovery.md | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/draft-ietf-quic-recovery.md b/draft-ietf-quic-recovery.md index a93ddf4514..e070fd70bd 100644 --- a/draft-ietf-quic-recovery.md +++ b/draft-ietf-quic-recovery.md @@ -751,11 +751,10 @@ twice the maximum datagram size. This follows the analysis and recommendations in {{?RFC6928}}, increasing the byte limit to account for the smaller 8 byte overhead of UDP compared to the 20 byte overhead for TCP. -If the maximum datagram size is decreased in order to complete the handshake, -the initial congestion window SHOULD be recalculated with the new smaller size -and the congestion window SHOULD be set to the smaller initial congestion -window. This avoids overly large initial congestion windows. The initial -window is not recalculated at any other time. +If the maximum datagram size changes during the connection, the initial +congestion window SHOULD be recalculated with the new size. If the maximum +datagram size is decreased in order to complete the handshake, the +congestion window SHOULD be set to the new initial congestion window. Prior to validating the client's address, the server can be further limited by the anti-amplification limit as specified in Section 8.1 of {{QUIC-TRANSPORT}}.