I noticed my internet connection has dropped to 10% capacity yesterday after working fine for 9 months. I have a linux machine acting as my router so I ran tcpdump and I'm being flooded with weird packets.
The MAC addresses involved aren't valid/registered.
I didn't see any obvious problems in the modem log (SB6121). So is this broken Comcast routing infrastructure?
08:22:26.076942 IP x.x.x.x.41435 > y.y.y.y.80: Flags [.], ack 188240, win 1109, options [nop,nop,TS val 550649051 ecr 2144839052], length 0
08:22:26.077069 IP y.y.y.y.80 > x.x.x.x.41435: Flags [.], seq 191136:192584, ack 1, win 122, options [nop,nop,TS val 2144839052 ecr 550649043], length 1448
08:22:26.077071 98:29:4f:db:00:01 > ea:05:15:fa:00:e0, ethertype Unknown (0x5c33), length 1518:
0x0000: 6b81 0800 4520 05dc aaff 4000 3606 5f09 k...E.....@.6._.
0x0010: 3274 3f41 3281 90bd 0050 a1db 4901 5d84 2t?A2....P..I.].
0x0020: 9094 0d04 8010 007a e220 0000 0101 080a .......z........
0x0030: 7fd7 a58c 20d2 3cd3 d0de f6e6 a644 d95c ......<......D.\
0x0040: b981 ed38 8d8a d920 0860 b4c2 77d5 d850 ...8.....`..w..P
0x0050: 5bbc 7411 e03f 7f85 843e 6888 ecef 881a [.t..?...>h.....
0x0060: 236c 12ed cd58 8d1a 4c4d 61b9 c8bd 0564 #l...X..LMa....d
0x0070: 7b81 4ff3 ac37 1834 d777 6924 1dd4 a2ac {.O..7.4.wi$....
0x0080: 392d ea0a 37c2 cbb1 83dc 137f 88ae a53e 9-..7..........>
0x0090: 0f7d 6c71 19df 9cd0 5ac9 d844 4449 4fe1 .}lq....Z..DDIO.
0x00a0: 79cd 141f a583 fb10 6669 19fd f069 08d1 y.......fi...i..
0x00b0: 33bd 4c8a 6f16 2248 4397 9e54 60c2 2c08 3.L.o."HC..T`.,.
0x00c0: 7835 42f4 387c fcc2 3a99 bf5e 75eb b2b8 x5B.8|..:..^u...
0x00d0: 9060 8d17 4330 ae09 6f24 c0a0 8e31 8fad .`..C0..o$...1..
0x00e0: 1596 cd62 74f5 a3d3 66da abbb f29f 69c1 ...bt...f.....i.
0x00f0: 190b ceff 5ce6 732f 93be 9ebc 27b9 8993 ....\.s/....'...
0x0100: bea3 0ae0 f7c6 5f92 9fae 0a80 8516 0712 ......_.........
0x0110: 6f20 f5e4 b7e4 f750 19fb f306 0085 f72e o......P........
0x0120: 4715 4a6e 1393 e8a1 8405 64c7 7a5e 32a2 G.Jn......d.z^2.
0x0130: 56af 04ed a4cb 89f1 c299 cecd 5998 3058 V...........Y.0X
0x0140: dafd 8d0a 6c0c 9b22 16f5 be89 40b3 f024 ....l.."....@..$
0x0150: 7e36 75d6 8561 6762 474b d1ae 276b c052 ~6u..agbGK..'k.R
0x0160: 43b5 4ec1 e32c 2131 175d 6ee0 4644 fe24 C.N..,!1.]n.FD.$
0x0170: 038f 7104 ef68 55ba 93db 5434 6ea0 3037 ..q..hU...T4n.07
0x0180: 8767 b8a7 aba0 48c5 bf63 6756 2ab2 5099 .g....H..cgV*.P.
0x0190: 6e68 89e8 1dd7 e9c7 069c 40ab d326 f794 nh........@..&..
0x01a0: 8958 398f d311 9f43 b19a 1bcb c686 d697 .X9....C........
0x01b0: 11d3 f10e fe7c 7663 c076 aacc 7ad1 53c5 .....|vc.v..z.S.
0x01c0: d3dc 6913 df0b 28a7 109c a6c2 241d cdfb ..i...(.....$...
0x01d0: 7f2f c5fc 9985 3d35 18fc 669d 74a8 3745 ./....=5..f.t.7E
0x01e0: e7fb 7459 4bc3 0056 69b2 755c 24bf a4ad ..tYK..Vi.u\$...
0x01f0: 9a57 ea73 aa4b 6331 7f2a d483 19c3 2a8e .W.s.Kc1.*....*.
0x0200: f4ef 5966 22cb bf99 0666 87c1 38ed bc43 ..Yf"....f..8..C
0x0210: 4a8c 432e 995d fe6e c270 711a d6b0 4fbd J.C..].n.pq...O.
0x0220: b279 df5b f29b fc9e 6eda 2226 33ae 9b9c .y.[....n."&3...
0x0230: d626 a604 578a 40ac 7753 eee4 3346 0549 .&..W.@.wS..3F.I
0x0240: f0c9 b04e 94d5 2b70 1ae4 815c d406 25e8 ...N..+p...\..%.
0x0250: 8db5 3896 7fd0 d200 b8a1 e86a 7136 2694 ..8........jq6&.
0x0260: 8d0c dc47 76a4 9d2a 10cd fabe 705a 1800 ...Gv..*....pZ..
0x0270: e8b8 e694 4e56 5054 8eaf 1178 cee4 388a ....NVPT...x..8.
0x0280: 6210 3325 b229 e03e cd45 79f4 8c19 e1d9 b.3%.).>.Ey.....
0x0290: 9e4e da1a bbbd 0d45 d196 7ac7 2dd5 1cee .N.....E..z.-...
0x02a0: 6b7d 5e6f 3862 91c2 1ea2 99a0 c0cb 73a0 k}^o8b........s.
0x02b0: 1618 6bf6 1f10 f32d 47d6 f78e ad07 e506 ..k....-G.......
0x02c0: 504c 60dd b18e c624 1584 4720 06b5 b3cb PL`....$..G.....
0x02d0: 7fbe b92e 3aae 8769 aff3 7801 1776 2588 ....:..i..x..v%.
0x02e0: a484 20ef 97c6 bb57 033b f06f ae24 a300 .......W.;.o.$..
0x02f0: d68c 064d 2e97 1dd8 8468 af07 64ef 5f57 ...M.....h..d._W
0x0300: cf14 878f 1933 8c48 195c b576 2b92 1cd9 .....3.H.\.v+...
0x0310: 4d82 29b7 891a 0107 8ec5 cca2 6b85 8468 M.).........k..h
0x0320: 4e37 d7cb bff3 de36 288d 07bb 328a eb04 N7.....6(...2...
0x0330: 5eb1 b546 177a ca45 3613 02fc 45b9 e867 ^..F.z.E6...E..g
0x0340: 018e afcc bce3 a82f 240e 58a5 da1a 946e ......./$.X....n
0x0350: 7df9 c764 e882 34d7 e199 cb2f f13b fdb7 }..d..4..../.;..
0x0360: c8be 9582 9bfa 8189 337d 5801 7377 024a ........3}X.sw.J
0x0370: 66ab 4fd1 707d 0902 663e 1cb1 2829 1c52 f.O.p}..f>..().R
0x0380: 655b 0587 d4a4 52d7 aa27 4742 4871 a49e e[....R..'GBHq..
0x0390: 1834 8c18 5993 bf79 f950 0d72 5c69 a13f .4..Y..y.P.r\i.?
0x03a0: 06ed 721f e6fa b576 9634 9218 f564 c621 ..r....v.4...d.!
0x03b0: 2f12 e4c2 ff6e f886 7795 5dbb aeeb 5958 /....n..w.]...YX
0x03c0: a81f 1821 2bd8 a996 5e77 74e9 6546 ab89 ...!+...^wt.eF..
0x03d0: dccf 7219 a098 2771 7a93 7238 6345 5104 ..r...'qz.r8cEQ.
0x03e0: e894 e04f 58ab 244f 8c63 3403 fd84 cf9f ...OX.$O.c4.....
0x03f0: 9588 b416 e7e8 eead c25e 8eeb e025 4ce5 .........^...%L.
0x0400: 7eeb 8b41 da97 9f45 938c 5977 c446 88bc ~..A...E..Yw.F..
0x0410: f0c9 db38 b178 24fc 130c e5e0 93f0 4d67 ...8.x$.......Mg
0x0420: f04c 53d1 8586 7045 e485 e005 24aa f0ee .LS...pE....$...
0x0430: 7364 3118 84a7 d416 39de f453 d142 5ce5 sd1.....9..S.B\.
0x0440: e047 e086 e8e2 25e1 7c8c bc2f 92fd 497e .G....%.|../..I~
0x0450: b4bf 5a5f ad2f d6f6 56c2 77ec ad59 fb2b ..Z_./..V.w..Y.+
0x0460: 5e77 083c 9aa9 ee5a 34e7 f395 f99e a62c ^w.<...Z4......,
0x0470: 87ec 98bd 9631 5243 8246 7179 6180 bbf3 .....1RC.Fqya...
0x0480: db7f 8149 ebe6 48c0 816a 1823 eda3 5b5d ...I..H..j.#..[]
0x0490: 8c1c 53f5 f562 cd20 4adf 7dd7 6503 b695 ..S..b..J.}.e...
0x04a0: 6e5e d8a4 0cb7 d6ad bea5 9ea4 500c bfab n^..........P...
0x04b0: 4aad d648 1d5a 15f8 f237 1483 616a c64c J..H.Z...7..aj.L
0x04c0: eedc ae30 7214 d08f 9229 4adf 6125 0853 ...0r....)J.a%.S
0x04d0: cdf4 4873 7430 ed5d 09a1 c668 648f a367 ..Hst0.]...hd..g
0x04e0: ccb4 b7ec e6f0 2409 3330 ae02 42ca f99e ......$.30..B...
0x04f0: dc4c 33ce 8ce2 c4b6 b34c 0ed3 d0d2 b3a1 .L3......L......
0x0500: 66b4 17fc 9474 db10 4a65 714f 1c96 1538 f....t..JeqO...8
0x0510: 538a db55 6a9c 4e20 453d a592 0219 8949 S..Uj.N.E=.....I
0x0520: 74a1 d665 3b49 cf0e 06b2 983b 9eea 5ea7 t..e;I.....;..^.
0x0530: 0d91 f17f 4b4c 20bc 635e f493 16aa 06d4 ....KL..c^......
0x0540: a00b c9b8 8fca aba8 5629 0271 7ae3 5d53 ........V).qz.]S
0x0550: 4fb5 77ab 53d2 f409 a59b 880e 2e84 cfb1 O.w.S...........
0x0560: fa60 21ab f156 6d66 e0c2 2f59 7537 58d2 .`!..Vmf../Yu7X.
0x0570: 1d0e b17b 3285 90f5 2469 14ea cec6 a026 ...{2...$i.....&
0x0580: 7909 61cc 26a2 344a 355e 1cd2 f963 b9e2 y.a.&.4J5^...c..
0x0590: e6c8 7f78 4f10 7ec2 4def 06e2 80e5 8c20 ...xO.~.M.......
0x05a0: e599 4bc0 445e 93aa 5ac3 0784 a483 efac ..K.D^..Z.......
0x05b0: cd2c 8d88 c537 66cc 1f1a a0df c266 2164 .,...7f......f!d
0x05c0: b98a 2a2d 13ae 17e5 c46c 8e93 21ab 2f0c ..*-.....l..!./.
0x05d0: 7a4a 0db9 3339 a765 6756 737a 4f24 991c zJ..39.egVszO$..
08:22:26.077150 IP x.x.x.x.41435 > y.y.y.y.80: Flags [.], ack 191136, win 1109, options [nop,nop,TS val 550649051 ecr 2144839052], length 0
08:22:26.077437 IP y.y.y.y.61076 > x.x.x.x.22: Flags [.], ack 109672, win 408, options [nop,nop,TS val 208760027 ecr 107862672], length 0
08:22:26.077438 98:29:4f:db:00:01 > 42:00:bd:ff:00:e0, ethertype Unknown (0x5c33), length 70:
0x0000: 6b81 0800 4520 0034 c228 4000 3306 cf7b k...E..4.(@.3..{
0x0010: 4a07 a8ba 3281 90bd ee94 0016 349b 429a J...2.......4.B.
0x0020: 762b ee00 8010 0198 9ace 0000 0101 080a v+..............
0x0030: 0c71 6cdb 066d da90 .ql..m..