Packet Buffer Sizing Resources

This page is a curated archive of resources related to packet buffer sizing in network equipment. Much of this information is derived from Jim Warner’s packet buffer page at UCSC, which notes that “information here is by rumor, innuendo and extrapolation.” Manufacturers historically left buffer information out of their data sheets, though this situation has improved significantly.

Background

Information here is by rumor, innuendo and extrapolation. Manufacturers used to leave info on packet buffers out of their data sheets. This situation is now much improved. Readers – be sure to let your suppliers know that you want this info. There are some summary thoughts .

The buffer size question discussed in 2012 on the NANOG list is reproduced. Buffer requirements for long RTT networks is less well understood than you might hope. IETF tests for burst management are not as well developed as bandwidth tests. Packet pacing can improve buffer effectiveness by making TCP less bursty. Cisco wrote a review of the buffer question in 2017. Geoff Huston wrote Sizing the Buffer, a review published as a blog entry in 2019.

Packet buffers and switch performance have shown steady improvement. The table below attempts to show this for ASICs with integrated packet buffers and why using crufty old stuff is at your peril.

Incast is a buffer exhaustion phenomena that is one consequence of running out of packet memory.

Shared memory means that the hardware permits buffers to be used by any port that needs them. In a shared memory design it is not possible to let ALL the memory go to queued packets. There would be no room for new arrivals which would lead to head of line blocking. The other major option for a switch fabric is a crossbar matrix.

Buffer queue depth monitoring cannot be done directly with SNMP MIB-II polling of the current occupancy of the buffer. Even if a buffer depth SNMP poll object existed it would not possible to interrogate it on a time scale short enough to catch microbursts. A burst that would fill a 4 MByte buffer would completely drain in 3.2 mS at 10 Gb/s. You could hope for indirect evidence of buffer exhaustion by monitoring packet drops. Bursts too short to cause drops can nonetheless be long enough to affect performance. Direct queue monitoring can thus add valuable information.

Some switches have multiple switch ICs that each manage their own memory pool. Memory from one IC can be shared among the ports in that IC’s group but cannot be loaned out to ports controlled by other switch chips. Here we are interested in queue resources that can be claimed by a single flow for burst absorption – not the total RAM in the system.

Tolly occasionally reports on the ability of switches to sustain microbursts in his reports on data center switches. These measurements relate directly to output port buffering.

Max buffer queue depth requires that all packet memory can be put into a single queue. QoS schemes divide buffer resources among defined queues.

Switch Buffer Specifications by ASIC Family

Trident+ Shared Memory

Model	Port Type	RX Queue	Total Buffer	TX Buffer
Accton 5652	48 SFP+ and 4 QSFP+	8Q	9 MB	5? MB
Juniper QFX3500	48 SFP+ and 4 QSFP+	8Q	9 MB	5 MB
Arista 7050S-64	48 SFP+ and 4 QSFP	8Q	9 MB/switch	5 MB
Dell 8132F & 4032F	24 SFP+ and 2 x QSFP+	8Q	9 MB
Dell 8164F & 4064F	48 SFP+ and 4 x QSFP+	8Q	9 MB
Pica8 P-3922	48 SFP+ and 4 x QSFP+		9 MB
Pica8 P-3930	48 10GbaseT and 4 x QSFP+		9 MB
Penguin 4804x	48 SFP+ and 4 x QSFP+		9 MB
Cisco Nexus 3064X	48 SFP+ and 4 QSFP+	12Q	9 MB	5 MB
Supermicro SSE-X3348T	48 10GTw-Pr and 4 QSFP+	8Q	9 MB
Supermicro SSE-X3348S	48 SFP+ and 4 QSFP+	8Q	9 MB
IBM G8264	48 SFP+ and 4 QSFP+	8Q	9 MB/switch
Force10 S4810	48 SFP+ and 4 QSFP+	4Q	9 MB
Allied Telesis DC2552	48 SFP+ and 4 QSFP+	8Q	9 MB	5 MB
HP 5900AF-48XG-4QSFP+	48 SFP+ and 4 QSFP+		9 MB
Edgecore AS5600-52X	48 SFP+ and 4 QSFP+		9 MB
Cisco Nexus 3048	48 1000-base-T and 4 SFP+	8Q	9 MB	5? MB
Brocade VDX 6740	48 SFP+ and 4 QSFP+		24 MB	Dynamic up to 8 MB
Brocade VDX 6940	96 SFP+ and 12 QSFP+		24 MB	Dynamic up to 8 MB

Trident II and II+

Model	Port Type	RX Queue	Total Buffer	TX Buffer
Champion Trident2	varies by model		12.2 MB
Lenovo G8272	48 SFP+ and 6 QSFP+		12.2 MB
Arista 7050X	32 QSFP+	8Q	12 MB	Dynamic up to 8 MB
Arista 7250X	64 QSFP+	8Q	12 MB/ASIC, 48 MB total	Dynamic up to 8 MB
netberg Aurora 420	48 SFP+ and 6 QSFP+	8Q	12 MB	Dynamic up to 8 MB
Arista 7300X 4/8/16 slot chassis	16 slot: 512 QSFP	8Q	12 MB/ASIC	Dynamic up to 8 MB
Brocade 7750-26Q	26 QSFP+ and slot	8Q	12.2 MB	Dynamic up to 8 MB
Brocade 7750-48F	48 SFP+ and 6 QSFP+ and expansion	8Q	12.2 MB	Dynamic up to 8 MB
Brocade 7750-48C	48 10GbaseT and 6 QSFP+ and expansion	8Q	12.2 MB	Dynamic up to 8 MB
Quanta BMS T3048-LY8	48 SFP+ and 4 QSFP+	8Q	12 MB	8 MB
Pluribus E68	44 SFP+ and 6 QSFP+	8Q	12 MB
Cisco Nexus 3132Q	32 QSFP+ or 31 QSFP+ and 4 SFP+	8Q	12.2 MB	Dynamic up to 8 MB
Cisco Nexus 3172PQ	48 SFP+ and 6 QSFP+	8Q	12.2 MB	Dynamic up to 8 MB
Dell-S4048-ON	48 SFP+ and 6 QSFP+	8Q	12 MB	Dynamic up to 8 MB
Dell S6000	32 QSFP+	8Q	12 MB	Dynamic up to 8 MB
Juniper QFX5100-24Q	24 QSFP+ + expansion slots	8Q	12 MB	Dynamic up to 8 MB
Juniper EX4600	24 SFP+ + 4 QSFP + expansion slots	8Q	12 MB	Dynamic up to 8 MB
HP 5930	32 QSFP+	8Q	12.2 MB	Dynamic up to 8 MB
HP Altoline 5712	48 SFP+ and 6 QSFP+	8Q	12.2 MB	Dynamic up to 8 MB
HP Altoline 6712	32 QSFP+	8Q	12.2 MB	Dynamic up to 8 MB
Accton edgecore AS5712-54X	48 SFP+ and 6 QSFP+	8Q	12.2 MB	Dynamic up to 8 MB
Accton edgecore AS6712-32X	32 QSFP+	8Q	12.2 MB	Dynamic up to 8 MB
Supermicro SSE-X3648S	48 SFP+ and 6 QSFP+	8Q	12.2 MB	Dynamic up to 8 MB
Inventec D6232Q	48 SFP+ and 6 QSFP+	8Q	12.2 MB	Dynamic up to 8 MB
Wedge - Facebook OCP	16 QSFP+	8Q	12.2 MB	Dynamic up to 8 MB

Trident II+

Model	Port Type	RX Queue	Total Buffer	TX Buffer
Alpha Networks SNX-60x0-486x	48 SFP+ and 4 QSFP28 100G and 2 QSFP+	8Q	16 MB	Dynamic up to 12 MB
Artica 4806xp	48 SFP+ and 6 QSFP 40G	8Q	16 MB	Dynamic up to 12 MB
Champion Trident2+	Three switch configurations	8Q	16 MB
Arista 7050X2 family	see table	8Q	16 MB	Dynamic up to 12 MB
Dell S4048T-ON	48 10G-BASE-T and 6 x QSFP+	8Q	16 MB	Dynamic up to 12 MB
Dell S6010-ON	32 40-Gbps QSFP	8Q	16 MB	Dynamic up to 12 MB
Cisco Nexus 3132Q-V	32 QSFP+ or 26 QSFP+ and 6 QSFP28	8Q	16 MB	Dynamic up to 12 MB
Cisco Nexus 31108PC-V	48 SFP+ and 6 QSFP28	8Q	16 MB	Dynamic up to 12 MB
Cisco NCS5001	40 1/10-Gbps SFP+ and 4 QSFP28 100G	8Q	16 MB	Dynamic up to 12 MB
Cisco NCS5002	80 1/10-Gbps SFP+ and 4 QSFP28 100G	8Q	16 MB	Dynamic up to 12 MB
EdgeCore AS6812-32X	32 40-Gbps QSFP+	8Q	16 MB	Dynamic up to 12 MB
Accton edgecore AS5812-54X	48 SFP+ and 6 QSFP+	8Q	16 MB	Dynamic up to 12 MB
Huawei CE6855-48S6Q-HI	48 SFP+ and 6 QSFP+	8Q	16 MB	Dynamic up to 12 MB
Huawei CE6855-48T6Q-HI	48 10G base-T and 6 QSFP+	8Q	16 MB	Dynamic up to 12 MB
HPE Altoline 6921-54X	48 SFP+ and 6 QSFP+	8Q	16 MB??	Dynamic up to 12 MB
Juniper QFX5110-48S	48 SFP+ and 4 QSFP28 100G	8Q	16 MB	Dynamic up to 12 MB
Juniper QFX5110-32Q	20 QSFP+ and 4 QSFP28 100G or 32 QSFP+	8Q	16 MB	Dynamic up to 12 MB

Trident 3

Model	Port Type	RX Queue	Total Buffer	TX Buffer
Arista 7050CX3-32S	32 port 100G QSFP28 and 2 port 10 Gb/s	8Q	32 MB	27 MB shared pool
Arista 7050SX3-48YC8	48 port 25G SFP28 and 8 port 100 Gb/s	8Q	32 MB	27 MB shared pool
Ragile RA-BS6510-48V8C	48 port 25G SFP28 and 8 port 100 Gb/s	8Q	32 MB	27 MB shared pool
Celestica Seastone2 Trident3 X7	32 port 100G QSFP28 and 2 port 10 Gb/s	8Q	32 MB	27 MB shared pool
Celestica Questone2 Trident3 X5	48 port 25G SFP28 and 8 port 100 Gb/s	8Q	32 MB	27 MB shared pool
Edgecore AS7326-56X BCM56873	48 port 25G SFP28 and 8 port 100 Gb/s	8Q	32 MB
Edgecore AS7726-32X BCM56870	32 port 100 Gb/s	8Q	32 MB
Edgecore AS5835-54X BCM56771	48 port 10G SFP+ and 6 port 100 Gb/s	8Q	32 MB
Edgecore AS5835-54T BCM56771	48 port 10 GBase-T and 6 port 100 Gb/s	8Q	32 MB
Edgecore AS4630-54PE BCM56371	48 X 1000BaseT and 4 X 25 Gb/s SFP28 and 2 x 100Gb/s QSFP28	8Q	8 MB
Arista 720XP family Trident X3	48 and 24 port, models with uplinks and PoE (varies)		8 MB	6 MB
Delta/Agema AGV424 BCM56771	24 port 25 Gb/s SFP28 and 4 port 100 Gb/s	8Q	32 MB
Extreme SLX9150	48 port 25G SFP28 and 8 port 100 Gb/s	8Q	32 MB
Extreme SLX9250	32 port 100 Gb/s	8Q	32 MB
Inventec D6356	48 port 25G SFP28 and 8 port 100 Gb/s	8Q	32 MB
Inventec D6332	32 port 100G QSFP28	8Q	32 MB
FS.COM N5860-48SC	48 port 10G SFP+ and 8 port 100 Gb/s	8Q	32 MB
FS.COM N8560-48BC	48 port 25G SFP28 and 8 port 100 Gb/s	8Q	32 MB
Juniper QFX5120-48T	48 port 10G Tw-Pr and 6 port 100 Gb/s	8Q	32 MB	24 MB
QuantaMesh BMS T4048-IX8	48 port 25G SFP28 and 8 port 100 Gb/s	8Q	32 MB
QuantaMesh BMS T7032-IX7	32 port 100G QSFP28	8Q	32 MB
Alpha SNC-60x0-488F	48 port 25G SFP28 and 8 port 100 Gb/s	8Q	32 MB
Lenovo ThinkSystem NE2580o	48 port 25G SFP28 and 8 port 100 Gb/s	8Q	32 MB
Huawei CE6857-48S6CQ-EI Trident3 X4	48 port 10 Gb/s SFP+ and 6 100 Gb/s QSFP28	8Q	32 MB
Huawei CE6865-48S8CQ-EI Trident3 X5	48 port 25 Gb/s SFP28 and 8 100 Gb/s QSFP28	8Q	32 MB
Dell S5212-ON	12 port 25 Gb/s SFP28 and 3 100 Gb/s QSFP28	8Q	32 MB
Dell S5224-ON	24 port 25 Gb/s SFP28 and 4 port 100G QSFP28	8Q	32 MB
Dell S5232-ON	32 port 100 Gb/s QSFP28	8Q	32 MB
Dell S5248-ON	48 port 25 Gb/s SFP28 and 4 100 G QSFP28 and 2 200 G QSFP	8Q	32 MB
Dell S5296-ON	96 x 25 Gb/s SFP28 and 8 x 100 G QSFP28	8Q	32 MB
Delta 9032v2	32 port 100 Gb/s QSFP28	8Q	32 MB
Cisco C3132C-Z	32 port 100 Gb/s QSFP28	8Q	32 MB
Ruckus ICX 7850-32Q	32 x QSFP28 100 Gb/s ports		32 MB
Ruckus ICX7850-48FS	48 x SFP+ 1/10 Gb/s and 8 x QSFP28 100 G ports		32 MB
Ruckus ICX 7850-48F	48 x SFP28 1/10/25 Gb/s and 8 x QSFP28 100 G		32 MB

Trident 4

Model	Port Type	Total Buffer
Arista 7050PX4-32S	32 x OSPF	132 MB
Arista 7050DX4-32S	32 x QSFP56-DD	132 MB
Arista 7358X4	8 slot 16- and 4- port cards	132 MB
Juniper QFX5130	32 x QSFP56-DD	132 MB
Dell Z9432F-ON	32 x QSFP56-DD	132 MB
Aurora 830 BCM56880	32 x QSFP56-DD	132 MB
ufiSpace S9300-32D BCM56880	32 x QSFP56-DD	132 MB
Ragile RA-B6520-24DC8QC BCM56780	8 x QSFP56-DD 400G and 24 × QSFP56 200G	82 MB
Ragile RA-B6520-48C8QC BCM56780	8 x QSFP56-DD 400G and 48 × DSFP56 100G	82 MB

Nephos 8360 Taurus Family

Model	Port Type	RX Queue	Total Buffer
Netberg Aurora 705 NP8367	32 port 100 Gb/s QSFP28	8Q	28 MB
Netberg Aurora 740 NP8369	64 port 100 Gb/s QSFP28	8Q	40 MB
CIG CS-6436-56P NP8366	48 port 25 Gb/s and 8 ports 100G QSFP28	8Q	24 MB
Liteon-LS3048-SN1 NP8363	48 port 10G SFP+ and 6 port 100 Gb/s	8Q	20 MB
Liteon-LS4048-SN3 NP8365	48 port 25G SFP28 and 6 port 100 Gb/s	8Q	20 MB
Nephos-AS7116-54X NP8365	48 port 25G SFP28 and 6 port 100 Gb/s	8Q	options: 20-50 MB
Ingrasys S9130-32X	32 port 100G QSFP28	8Q	options: 20-50 MB
Ingrasys S9230-32X	64 port 100G QSFP28	8Q	options: 20-50 MB

Broadcom Maverick

Model	Port Type	RX Queue	Total Buffer	TX Buffer
Alpha Networks SNX-61A0-486T	48 10G-base-T and 4 QSFP28 and 2 QSFP	8Q	?? MB
Alpha Networks SNX-61A0-486F	48 SFP+ and 4 QSFP28 and 2 QSFP	8Q	?? MB
Dell S4148F-ON	48 port SFP+ and 2 QSFP+ and 2 QSFP28	8Q	12 MB	8 MB
Dell S4148T-ON	48 port 10BaseT and 2 QSFP+ and 2 QSFP28	8Q	12 MB	8 MB
Dell S4112F-ON and S4112T-ON	12 port SFP28 and 3 QSFP28	8Q	12 MB	8 MB
QCT QuantaMesh T3048 LY7	48 port SFP+ and 4 QSFP28	8Q	12 MB	8 MB

Broadcom Tomahawk

Model	Port Type	RX Queue	Total Buffer	TX Buffer
Penguin 3200C	32 port QSFP28 100 Gb/s	8Q	16 MB	Est 3 MB per core
Dell Z9100	32 port QSFP28 100 Gb/s	8Q	16 MB	Est 3 MB per core
Dell S6100-ON	Depends on modules selected	8Q	16 MB	Est 3 MB per core
Dell S5148	48 port SFP28 25 Gb/s + 6 x 100G	8Q	16 MB	Est 3 MB per core
Cisco Nexus 3232C	32 port QSFP28 100 Gb/s	8Q	16 MB	Est 3 MB per core
Cisco NCS5011	32 QSFP28 100G	8Q	16 MB	Est 3 MB per core
Arista 7060CX-32	32 port QSFP28 100 Gb/s and 2 SFP+	8Q	16 MB	Est 3 MB per core
Arista 7260CX-64	64 port QSFP28 100 Gb/s and 2 SFP+	8Q	64 MB	Est 3 MB per core
Arista 7320X	256 port QSFP28 100 Gb/s	8Q	64 MB	Est 3 MB per core
Juniper QFX5200-32C	32 port QSFP28 100 Gb/s	8Q	16 MB	Est 3 MB per core
Juniper QFX5200-64Q	32 port QSFP28 OR 64 QSFP	8Q	16 MB	Est 3 MB per core
Aurora 620 with ONIE	48 SFP28 25 Gb/s and 6 QSFP28 100 G	8Q	16 MB	Est 3 MB per core
Aurora 630 with ONIE	48 SFP28 25 Gb/s and 16 QSFP28 100 G	8Q	16 MB	Est 3 MB per core
Aurora 720 with ONIE	32 QSFP28 100 Gb/s	8Q	16 MB	Est 3 MB per core
Inventec D7032Q28B	32 QSFP28 100 Gb/s	8Q	16 MB	Est 3 MB per core
Edgecore AS7710 and AS7712	32 QSFP28 100 Gb/s	8Q	16 MB	Est 3 MB per core
Edgecore OMP800	256 QSFP28 100 Gb/s	8Q	16 MB	Est 3 MB per core
Ragile RA-B6500-32H	48 X 50 Gb/s and 8 x QSFP28 100 Gb/s		16 MB	Est 3 MB per core
HP 6960	32 QSFP28 100 Gb/s	8Q	16 MB	Est 3 MB per core
Quanta T7032-IX1	32 x QSFP28 100Gb/s	8Q	16 MB	Est 3 MB per core
Quanta T4048-IX2	48 x SFP28 + 8 x QSFP28	8Q	16 MB	Est 3 MB per core
Agema AG5648	6 QSFP28 100 Gb/s and 48 SFP28 25 Gb/s	8Q	16 MB	Est 3 MB per core
Supermicro SSE-C3632S	32 QSFP28 100 Gb/s	8Q	16 MB	Est 3 MB per core
Agema AG9032	32 QSFP28 100 Gb/s	8Q	16 MB	Est 3 MB per core
Facebook OCP Backpack	128 QSFP28 100 Gb/s	8Q	256 MB	Est 3 MB per core

Broadcom Tomahawk+

Model	Port Type	RX Queue	Total Buffer	TX Buffer
fs.com N8500-48B6C	48 SFP28 25 Gb/s and 6 QSFP28 100 Gb/s	8Q	16 MB
Juniper QFX5200-48Y	48 SFP28 25 Gb/s and 6 QSFP28 100 Gb/s	8Q	22 MB
Agema AG5648V1	48 SFP28 25 Gb/s and 6 QSFP28 100 Gb/s	8Q	16 MB
Edgecore AS7312-54XS	48 SFP28 and 6 QSFP28	8Q	22 MB	Est 4.5 MB per core
Alpha Networks SNC-60x0-486F	48 SFP28 25 Gb/s and 6 QSFP28 100 Gb/s	8Q	22 MB
Arista 7060CX2-32S	32 QSFP28 100 Gb/s AND 2 SFP+	8Q	22 MB	Est 4.5 MB per core
Lenovo NE2572 & NE2572O	48 SFP28 25 Gb/s AND 6 QSFP28	8Q	22 MB	Est 4.5 MB per core

Broadcom Tomahawk-II

Model	Port Type	RX Queue	Total Buffer	TX Buffer
Arista 7260QX-64	64 QSFP 40 Gb/s AND 2 SFP+	8Q	16 MB	Est 3 MB per core
Arista 7260CX3-64	64 QSFP28 100Gb/s AND 2 SFP+	8Q	42 MB	10.5 MB per slice
Agema AG9064	64 QSFP28 100 Gb/s	8Q	16 MB	Est 3 MB per core
Edgecore AS7816-64X	64 QSFP28 100 Gb/s	8Q	42 MB	Est 10.5 MB per slice
Cisco Nexus C3264C-E	64 QSFP28 100 Gb/s AND 2 SFP+	8Q	42 MB	Est 10.5 MB per slice
Juniper QFX5210-64C	64 QSFP28 100 Gb/s AND 2 SFP+	8Q	42 MB	Est 10.5 MB per slice
Dell Z9264f-ON	64 QSFP28 100 Gb/s AND 2 SFP+	8Q	42 MB	Est 10.5 MB per slice
FS.COM N8560-64	64 QSFP28 100 Gb/s AND 2 SFP+	8Q	42 MB	Est 10.5 MB per slice
Ragile RA-B6910-64C	64 QSFP28 100 Gb/s	8Q	42 MB	Est 10.5 MB per slice

Broadcom Tomahawk 3

Model	Port Type	Total Buffer
Edgecore AS7900-32X & AS9716-32D	32 x QSFP-DD 400 Gb/s ports	64 MB
Arista 7060PX4-32	32 x OSFP 400 Gb/s ports and 2 x SFP+	64 MB
Arista 7060DX4-32	32 x QSFP-DD 400 Gb/s ports and 2 x SFP+	64 MB
Facebook Minipack	8-slot chassis: 4x400 Gbps and 16x100 Gbps cards	64 MB
Arista 7368X4	8-slot chassis: 4x400 Gbps and 16x100 Gbps cards	64 MB
QuantaMesh BMS 9032-IX9	32 x QSFP-DD 400 Gb/s ports	64 MB
Delta AGC032	32 x QSFP-DD 400 Gb/s ports and 2 x SFP+	64 MB
Dell Z9332F-ON	32 x QSFP-DD 400 Gb/s ports and 2 x SFP+	64 MB
Aurora 820	32 x QSFP-DD 400 Gb/s ports	64 MB
Ragile RA-B6920-32QC2X	32 x QSFP-DD 400 Gb/s ports and 2 x SFP+	64 MB
Ragile RA-B6920-4S	4 slots, 32 x QSFP 100 Gb/s cards	64 MB

Tomahawk-4

Model	Port Type	Total Buffer	TX Buffer
Arista 7060X5	64 x QSFP-DD 400 Gb/s ports and 2 SFP+	113 MB	113 MB
Arista 7388X5	8-slot chassis: 8- and 16-port cards	113 MB	113 MB
Ragile RA-B6930-64QC	64 x QSFP-DD 400 Gb/s ports	113 MB
Ragile RA-B6930-128DC	128 x QSFP 200 Gb/s ports	113 MB

Innovium Teralynx

Model	Port Type	Total Buffer
Aurora Netberg 615	48 x SFP28 25 Gb/s ports + 8 x QSFP28 100 Gb/s	45 MB
Aurora Netberg 715	32 x QSFP28 100 Gb/s ports	45 MB
Cisco Nexus 3408-S	8-slot chassis w 4-port 400G and 16-port 100G cards	70 MB
Cisco Nexus 3432D-S	32 port QSFP-DD 400 Gb/s + 2 x SFP	70 MB

Broadcom Jericho (StrataDNX DUNE family)

Model	Port Type	Total Buffer	Notes
Cisco NCS 5508	288 QSFP28 100 Gb/s ports	4 GB per ASIC	VoQ 10 mS per queue
Cisco Nexus N9K-X9636C-R	36 x 100 Gb/s QSFP28 linecard	4 GB per ASIC	VoQ
Cisco Nexus N9K-X9636Q-R	36 x 40 Gb/s QSFP linecard	4 GB per ASIC	VoQ
Arista 7500R Linecard 36CQ	36 x QSFP28 100G	24 GB	VoQ
Arista 7500R Linecard 36Q	30 x 40G QSFP and 6 x 100G	8 GB	VoQ
Arista 7500R Linecard 48S2CQ	48 port sfp+ and 2 x 100G	4 GB	VoQ
Arista 7280QR-C36	24 QSFP+ and 12 QSFP28	8 GB in 2 groups	VoQ
Arista 7280QR-C48	48 QSFP+ and 24 QSFP28	32 GB in 8 groups	VoQ
Brocade SLX-9850	36 QSFP28 per linecard	4 or 6 GB per 6-port group	VoQ

Broadcom Qumran (StrataDNX DUNE family)

Model	Port Type	RX Buffer	Notes
Arista 7020SR-24C2	24 x 10G SFP+ and 2 x QSFP28	3 GB	VoQ
Arista 7020SR-32C2	32 x 10G SFP+ and 2 x QSFP28	3 GB	VoQ
Arista 7020TR-48	48 x 1GBASE-T and 6 x SFP+	3 GB	VoQ
Arista 7280SR-48C6	48 x 10 G SFP+ and 6 x QSFP28	4 GB	VoQ
Arista 7280TR-48C6	48 x 10GBASE-T and 6 x QSFP28	4 GB	VoQ
Cisco NCS 5501	six QSFP28 100 Gb/s ports and 48 x 10 Gb/s	4 GB per ASIC	VoQ 10 mS per queue
Brocade SLX-9540 / Extreme SLX-9540	6 QSFP28 100/40 Gb/s and 48 10/1 Gb/s	6 GB	VoQ
Extreme SLX-9640	12 QSFP28 100/40 Gb/s and 24 10/1 Gb/s	6 GB	VoQ
Edge-Core AS5912-54X	48 SFP+ and 6 QSFP28 Qumran-MX BCM88370	6 GB	VoQ
Edge-Core AS5916-54XKS	48 SFP+ and 6 QSFP28 Qumran-MX BCM88375	8 GB	VoQ
Edge-Core AS5916-54XL	48 SFP+ and 6 QSFP28 Qumran-MX BCM88370	8 GB	VoQ
HPE FlexFabric 5980	48 SFP+ and 6 QSFP28	4 GB	VoQ
Champion Qumran	48 SFP+ and 6 QSFP28	4 GB	VoQ
Alpha STX-60x0-486F Qumran	48 SFP+ and 6 QSFP28	4 GB	VoQ
Dell S4248-ON	48 SFP+ and 6 QSFP28	4 GB	VoQ
Agema AGC7648A BCM88375	48 SFP+ and 6 QSFP28	4 GB	VoQ

Disaggregated Cell Site Gateways

Model	Port Type	Buffer	Notes
ufiSpace S9500-22XST	4 x 1G RJ-45, 8 x 10G SFP+, 8 x 25G SFP28, 2 x 100G QSFP28	2 GB QumranAX BCM88470	VoQ
ufiSpace S9500-30XS	20 x 10G SFP+, 8 x 25G SFP28, 2 x 100G QSFP28	3 GB QumranAX BCM88470	VoQ
Delta AGCV208S	4 x 1G RJ45/ 4 x 10G SFP+/ 8 x 25G SFP28/ 2 x 100G QSFP28	1 GB QumranAX BCM88470	VoQ
Edgecore AS7316-26XB aka CSR320	16 x 10G SFP+, 8 x 25G SFP28, 2 x 100G QSFP28	3 GB QumranAX BCM88470	VoQ
Edgecore AS7315-27X aka CSR310	20 x 10G SFP+, 4 x 25G SFP28, 3 x 100G QSFP28	3 GB QumranAX BCM88470	VoQ
Edgecore AS7315-30X aka CSR300	4 x 1G RJ45, 16 x 10G SFP+, 8 x 25G SFP28, 2 x 100G QSFP28	3 GB QumranAX BCM88470	VoQ
Edgecore AS5915-18X aka CSR200	4 x 1G RJ45, 8 x 1G SFP, 6 x 10G SFP+	2 GB QumranUX BCM88272	VoQ
ufiSpace S9501-18SMT	4 x 1G RJ45, 8 x 1G SFP, 6 x 10G SFP+	1 GB QumranUX BCM88272	VoQ
ufiSpace S9501-28SMT	4 x 1G RJ45, 16 x 2.5G SFP, 6 x 10G SFP+, 2 x 10G SFP+ MACsec	1 GB QumranUX BCM88272	VoQ

Broadcom Qumran-2C (StrataDNX DUNE family)

Model	Port Type	Buffer	Notes
Agema AGCX422S	22 x QSFP28 100G + 4 x QSFP-DD 400G + 4 x SFP28 10G/25G		VoQ
Agema AGCVA48S	48 x SFP28 + 4 x SFP+ 10G + 10 x QSFP28 100G	4 GB	VoQ
UfiSpace S9600-32X	32 x QSFP28 100G	4 GB	VoQ
Edge-core AS7946-30XB	22 x QSFP28 100G + 4 x QSFP-DD 400G + 4 x SFP28 10G/25G	4 GB	VoQ

Broadcom Jericho+ (StrataDNX DUNE family)

Model	Port Type	Buffer	Notes
Agema AGC5648 Jericho+	48 SFP28 and 6 QSFP28	8 GB per ASIC	VoQ
Cisco 3636C-R	36 ea QSFP28 100 Gb/s	4 GB per ASIC	VoQ
Cisco NCS-55A1-36H-S/SE	36 ea QSFP28 100 Gb/s	4 GB per ASIC	VoQ
Cisco NCS-55A1-24H-S/SE	24 ea QSFP28 100 Gb/s	4 GB per ASIC	VoQ
Arista 7280SR2A-48YC6	48 x 25 G SFP28 and 6 x QSFP28	8 GB	VoQ
Arista 7500R2-36CQ	36 x QSFP28 100 Gb/s	4 GB per ASIC	VoQ

Broadcom Jericho2 (16 nm StrataDNX DUNE family)

Model	Port Type	Buffer	Notes
Edgecore AS7926-80X	80 x QSFP28 100 Gb/s	8 GB	VoQ
Edgecore AS9926 Sw Fabric	24 x 400Gb/s QSFP-DD	?	VoQ
Edgecore AS7926-40XKFB	40 x QSFP28 100 Gb/s + 13 x QSFP-DD 400 Gb/s	8 GB	VoQ
ufiSpace S9700-53DX	40 x QSFP28 100 Gb/s ports + 13 x QSFP-DD 400 Gb/s fabric	8 GB	VoQ
ufiSpace S9600-48X	48 x QSFP28 100 Gb/s	8 GB	VoQ
ufiSpace S9700-23D	10 x 400 Gb/s QSFP-DD ports and 13 x 400 G QSFP-DD fabric	8 GB	VoQ

Arista 7280xR3 (Jericho2 switches)

Model	Port Type	Buffer	Notes
7280CR3-32P4	32 ports QSFP28 100G + 4 ports OSFP 400G	8 GB - 1 Jericho2 ASIC	VoQ
7280CR3-32D4	32 ports QSFP28 100G + 4 ports QSFP-DD 400G	8 GB - 1 Jericho2 ASIC	VoQ
7280PR3-24	24 ports 400 Gb/s, OSFP 400 G	16 GB - 2 Jericho2 ASICs	VoQ
7280DR3-24	24 ports 400 Gb/s QSFP-DD 400 Gb/s	16 GB - 2 Jericho2 ASICs	VoQ
7280CR3-96	96 ports QSFP28 100 Gb/s	16 GB - 2 Jericho2 ASICs	VoQ
Cisco NC57-24X400G-BA linecard	24 ports 400 Gb/s QSFP-DD	16 GB - 2 Jericho2 ASICs	VoQ
Cisco NC57-18D12TH-SB linecard	18 x 400 Gb/s or 30 x 100/200 Gb/s QSFP-DD	16 GB - 2 Jericho2 ASICs	VoQ

Broadcom Jericho2C+ (7 nm StrataDNX DUNE family)

Model	Port Type	Buffer	Notes
ufiSpace S9710-76D	36 x 400 Gb/s QSFP-DD ports and 40 x 400 G QSFP-DD fabric	16 GB	VoQ

Cisco 8000 Silicon One

Model	Port Type	Buffer	Notes
Cisco 8201 (Q100 ASIC)	24 QSFP56-DD 400 Gb/s and 12 QSFP28 100 Gb/s	8 GB	VoQ
Cisco 8202 (Q100 ASIC)	12 QSFP56-DD 400 GbE and 60 QSFP28 100 Gb/s	8 GB	VoQ
Cisco 8201-32FH (Q200 ASIC)	32 QSFP56-DD 400 GbE	8 GB	VoQ

Broadcom ARAD (StrataDNX DUNE family)

Model	Port Type	Buffer	Notes
Arista 7280E-64	48 port SFP+ and 4 x QSFP	9 GB	VoQ 125 MB per 10 gig port
Arista 7280E-68	48 port SFP+ and 2 x QSFP28 100 Gb/s	9 GB	VoQ 125 MB per 10 gig port
Arista 7280E-72	48 port SFP+ and 2 x MXP	9 GB	VoQ 125 MB per 10 gig port
Arista 7504E/7508E	48 port sfp+ line card	3 GB per each of 3 processors	VoQ
Arista 7504E Linecard 12CQ	12 QSFP28 100G	3 GB per each of 6 processors	VoQ

EZChip NP-5

Model	Port Type	Buffer	Notes
PARPRO N5R-100	24 SFP+ and 4 QSFP+	12 GB	VoQ very large
NoviSwitch 2122	20 SFP+ and 2 QSFP28	1 GB	VoQ very large
NoviSwitch 2128	20 SFP+ and 4 SFP+ and 4 QSFP+	1 GB	VoQ very large
NoviSwitch 2150	48 SFP and 2 QSFP+	1 GB	VoQ very large
NoviSwitch 21100	96 10/100/1000Base-T and 4 QSFP+	1 GB	VoQ very large

Cavium

Model	Port Type	TX Buffer
edgecore AS7500-32X	32 QSFP28 100 Gb/s	24 MB
edgecore AS7512-54X	6 QSFP28 100 Gb/s and 48 SFP28	24 MB
Wedge_100C	32 QSFP28 100 Gb/s	24 MB
Arista 7160 family	32 QSFP28 100 Gb/s	24 MB
Brocade SLX-9240	32 QSFP28 100 Gb/s	24 MB
Brocade SLX-9140	6 QSFP28 100 Gb/s and 48 QSFP28	24 MB
Pegatron w/out model num	6 QSFP28 100 Gb/s and 48 QSFP28	24 MB

Barefoot Tofino

Model	Port Type	Total Buffer	TX Buffer
Wedge 100BF-32X	32 x QSFP28 100G	16 MB	16 MB
Wedge 100BF-65X	65 x QSFP28 100G	16 MB	16 MB
OSW 1800	48 x SFP28 25G and 6 x QSFP28 100G	16 MB	16 MB
InterfaceMasters Tahoe 2624	20 x SFP28 25G and 26 x QSFP28 100G	22 MB	20 MB
Netberg Aurora 610 Tofino BFN-T10-032D	48 SFP28 25 Gb/s and 8 x QSFP28 100 Gb/s	22 MB	20 MB
Netberg Aurora 710 Tofino BFN-T10-032D	32 x QSFP28 and 2x SFP+	22 MB	20 MB
Netberg Aurora 750 Tofino BFN-T10-064Q	64 x QSFP28 and 2x SFP+	22 MB	22 MB
Arista 7170-64C	64 x QSFP28	22 MB	20 MB
Stordis BF2556XT-1T	48 x SFP28 and 8 x QSFP28	22 MB	20 MB
Stordis BF6064X-T	65 QSFP28 100 Gb/s	22 MB	20 MB
APS Networks APS2172Q	64 SFP28 1/10/25G and 8 QSFP28 100 Gb/s	22 MB	20 MB
APS Networks APS2140D	32 SFP28 1/10/25G and 8 QSFP28 100 Gb/s	22 MB	20 MB
APS Networks APS6120Q	16 QSFP28 100 Gb/s	22 MB	20 MB
Cisco Nexus C34180	48 x SFP28 and 6 x QSFP28	20 MB	20 MB
Arista 7170-32C	32 x QSFP28	22 MB	20 MB
ufiSpace S9180-32X	32 x QSFP28 + 2 x SFP+	22 MB	20 MB

Intel Tofino2

Model	Port Type	Total Buffer
Edgecore 9516-32D aka DCS810	32 x QSFP56-DD	64 MB

Mellanox Spectrum

Model	Port Type	RX Queue	Total Buffer	TX Buffer
Mellanox SX1024	48 SFP+ and 12 QSFP+		4.6 MB	64 KB to 1 port
Mellanox SX1036	36 QSFP+		4.6 MB	128 KB to 1 port
Mellanox SN2700 SN2410 SN2100	32 QSFP28 100Gb/s	8	16 MB	12 MB to 1 port?
Mellanox MSN2010-CB2RC	18 SFP28 25G and 4 QSFP28 100Gb/s	8	16 MB	12 MB to 1 port?
HPE SN2700M SN2410M SN2100iM	32 QSFP28 100Gb/s	8	16 MB	12 MB to 1 port?

Mellanox Spectrum-2

Model	Port Type	RX Queue	Total Buffer	TX Buffer
Mellanox SN3800	64 QSFP28 100Gb/s	16	42 MB	32 MB to 1 port?
Mellanox SN3700 and SN3700C	32 QSFP56 200Gb/s or QSFP28 100Gb/s	16	42 MB	32 MB to 1 port?
Mellanox SN3510	8 QSFP-DD 400 Gb/s + 48 QSFP56 50Gb/s	16	42 MB	32 MB to 1 port?
Mellanox SN3420	12 QSFP28 100Gb/s + 48 SFP28	16	42 MB	32 MB to 1 port?

Mellanox Spectrum-3

Model	Port Type	RX Queue	Total Buffer	TX Buffer
Mellanox SN4700	32 port QSFP-DD 400Gb/s	16	64 MB	50 MB to 1 port?
Mellanox SN4600	64 port QSFP56 200Gb/s	16	64 MB	50 MB to 1 port?
Mellanox SN4600C	64 port QSFP28 100Gb/s	16	64 MB	50 MB to 1 port?
Mellanox SN4800	8 slots: 4x400Gb/s, 8x200Gbs, 16x100Gb/s	16	64 MB	50 MB to 1 port?

Broadcom Helix

Model	Port Type	RX Queue	Total Buffer	TX Buffer
Arista 7010T	48 1000-base-T + 4 SFP+	8Q	4 MB/switch	4 MB
Brocade ICX 7150-24	(24+2) 1000-base-T and 4 SFP+	8Q	2 MB	2 MB to 1 port
Brocade ICX 7250-24	(24+2) 1000-base-T and 4 SFP+	8Q	2 MB	2 MB to 1 port
Brocade ICX 7650-48P	48 x 1000bsseT and (2 x 40G or 4 x 10G front module)	8Q	5 MB
Brocade ICX 7650-48ZP	24 x 1000BaseT and 24 multiGig ports and (1 x 100G or 2 x 40G)	8Q	12 MB
HPE Altoline 6900	48 1000-base-T and 4 SFP+ and 2 QSFP stacking ports	8Q	4 MB
Dell S3048-ON	48 1000-base-T and 4 SFP+	8Q	4 MB
Agema AG6248C	48 1000-base-T PoE+ w 2 SFP+	8Q	4 MB
Edgecore 4610-30T Helix4	24 1000-base-T w 4 SFP+ and 2 QSFP stacking ports	8Q	4 MB
Edgecore 4610-54T Helix4	48 1000-base-T w 4 SFP+ and 2 QSFP stacking ports	8Q	4 MB

Centec

Model	Port Type	Total Buffer
Centec V580-20Q4Z and E580-20Q4Z	20 x QSFP 40G and 4 x SFP+ and 4 x QSFP28 100G	9 MB
Centec V580-48X2Q4Z and E580-48X2Q4Z	48 x SFP+ 10G and 2 x QSFP+ 40G and 4 x QSFP28 100G	9 MB
Centec V350-48T4X and E350-48T4X	48 x 1000baeT and 4 x QSFP+ 40G and 4 x QSFP28 100G	3 MB
Centec E330-52SX	48 x SFP 1G and 4 x SFP+ 10G	6 MB

Cisco UADP Catalyst

Model	Port Type	RX Queue	Total Buffer	TX Buffer
Catalyst 3850, 3650	ASIC support 24 GE ports AND 2 x 10GE	8Q	6 MB per ASIC	4 MB per ASIC
Catalyst C3850-12XS	12 SFP+ (6 ports per ASIC)	8Q	6 MB per ASIC	4 MB per ASIC
Catalyst C9200-family	24- and 48-port 1-Gb/s access switches + uplinks	8Q	6 MB	4 MB
Catalyst C9300-24T	ASIC support 24 GE ports AND uplink module	8Q		~5 MB
Catalyst C9300-48T	48 GE ports AND uplink module	8Q		~5 MB
Catalyst C9300-24UX	24 100/1G/2.5G/5G/10G Tw-Pr ports AND uplink module	8Q		~5 MB
Catalyst C9500-24Q	24 QSFP 40 Gb/s	8Q		~10 MB
Catalyst C9500-40X	24 SFP+ ports AND uplink module	8Q		~10 MB
Catalyst C9500-24Y4C [UADP 3.0]	24 SFP28 ports AND 4 QSFP28 100G	8Q	36 MB per ASIC	est 23 MB
Catalyst C9500-32QC [UADP 3.0]	16 x QSFP28 100G OR 32 QSFP 40G	8Q	36 MB per ASIC	est 23 MB
Catalyst C9500-32C [UADP 3.0]	32 QSFP28 100G ports	8Q	36 MB per ASIC	est 23 MB
Catalyst C9500-48Y4C [UADP 3.0]	48 SFP28 ports AND 4 QSFP28 100G	8Q	36 MB per ASIC	est 23 MB
Catalyst C9600R	6-slot chassis w 3 ea UADP3.0 ASICs	8Q	36 MB per ASIC	est 23 MB

Cisco Nexus switches w ACI silicon

Model	Port Type	Total Buffer	TX Buffer
Cisco Nexus 92160YC-X	48 SFP28 and 6 QSFP28	Single ASE3 20 MB	10.2 MB
Cisco Nexus 9272Q	2RU 72 x 40Gb/s QSFP+	Single ASE2 30 MB	5.1 MB
Cisco Nexus 92304QC	2RU 56 x 40Gb/s QSFP+ and 8 QSFP28	Single ASE2 30 MB	5.1 MB
Cisco Nexus 9372TX	48 10-Gbps Base-T and 6 QSFP+	12 MB NFE + 25 MB ALE	21 MB max burst
Cisco Nexus 9396PX	48 SFP+ and {12 QSFP+ or 4 CPAK 100G}	12 MB NFE + 40 MB ALE	21 MB max burst
Cisco Nexus 93180YC-EX	48 SFP28 25 Gb/s and 6 QSFP28	2 slices x 20 MB	17.6 MB
Cisco Nexus 93108TC-EX	48 tw-pr 10 Gb/s and 6 QSFP28	2 slices x 20 MB	17.6 MB
Cisco Nexus 93180YC-FX	48 SFP28 25 Gb/s and 6 QSFP28	40 MB	~35 MB
Cisco Nexus 93108TC-FX	48 tw-pr 10 Gb/s and 6 QSFP28	40 MB	~35 MB
Cisco Nexus 9364C	64 ports QSFP28 100 Gb/s	40 MB	10 MB
Cisco Nexus 9332C	32 ports QSFP28 100 Gb/s	40 MB	10 MB
Cisco N9K-9336C-FX2	36 ports QSFP28 100 Gb/s	40 MB	20 MB
Cisco N9K-93360YC-FX2	96 x 10/25 Gb/s SFP28 + 12 x 40/100 Gb/s QSFP28	40 MB	20 MB
Cisco Nexus N9K-C9316D-GX	16 QSFP-DD 400/100 Gb/s	80 MB	20 MB
Cisco Nexus N9K-C93600CD-GX	28 SFP28 and 8 QSFP28-DD	80 MB	20 MB
Cisco Nexus 9364-GX2A	64 QSFP-DD + 2 SFP+	120 MB	30 MB per slice
Cisco Nexus 9332-GX2B	32 QSFP-DD + 2 SFP+	120 MB	60 MB per slice

Large Queue 1RU Switches

Model	Port Type	RX Queue	Total Buffer	Notes
Force10 S60	48 Gig-E + 4 SFP+	4Q	1250 MB	enough
Arista 7048	48 Gig-E + 4 SFP+	8Q	768 MB	GOBBS
Corsa DP2100	32 1/10 G SFP+	8Q	6 GB
Corsa DP2200	32 1/10 G SFP+ and 2 QSFP28 100G	8Q	6 GB
Corsa DP2400	32 1/10 G SFP+ and 2 QSFP28 100G + stack	8Q	6 GB
Corsa DP6430	24 SFP+ and 2 CFP/2 100G	8Q	20 GB
Corsa DP6440	48 SFP+ and 4 CFP/2 100G	8Q	20 GB

Virtual Output Port Queuing

Model	Port Type	RX Queue	Buffer	Notes
Brocade MLX	2-port 100 Gb/s line card	8Q	3 GB	256 MB/port-queue VoQ
Brocade MLX	8-port 10 Gb/s line card	8Q	3 GB	256 MB/port-queue VoQ
Brocade MLX	24-port 1 Gb/s line card	8Q	1 GB	64 MB/port-queue VoQ
Cisco Nexus 5010	26 SFP+	8	480 KB per port	VoQ
Cisco Nexus 5548P	32 fixed SFP+ and 16-port expansion module	8	640 KB per port	VoQ
Cisco Nexus 5672UP	48 fixed SFP+ and 6 QSFP+	8	25 MB per 12-port 10G ASIC	VoQ
Cisco Nexus 6001	48 fixed SFP+ and 4 QSFP+	8	25 MB per 12-port 10G ASIC	VoQ
Cisco ASR-9000	Chassis solution. 1-6 ports per ASIC		ASICs have 0.5 to 3.3 GB/port	VoQ
Juniper QFX10002-36	QSFP: 12 x 100 Gb/s OR 36 x 40 Gb/s	8Q	4 GB per ASIC	VoQ 100 mS per port

Nexus 7000/7700

Model	Port Type	RX Queue	TX Queue	Buffer
Cisco Nexus 7000 (M1 series)	48-port Tw-Pr GE	2q4t	1p3q4t	7.56 MB per port RX, 6.15 MB per port TX
Cisco Nexus 7000 (F3 Series)	6-port 100GE CPAK	4q	4q	72 MB shared, VoQ
Cisco Nexus 7000 (F2 series)	48 SFP+ across 12 ASICs	4q1t	1p3q1t	72 MB shared, VoQ
Cisco Nexus 7000 (F3 series)	12 QSFP+ across 6 ASICs	4q1t	1p3q1t	72 MB shared, VoQ
Cisco Nexus 7000 (M1 series)	32-port 10GE shared 4-port groups SFP+	8q2t	1p7q4t	65 MB per group RX, 80 MB per group TX
Cisco Nexus 7000 (M1 series)	8-port 10GE X2	8q2t	1p7q4t	92 MB RX, 80 MB TX
Cisco Nexus 7000 (M2 series)	2-port 100GE CFP2	8q2t	1p7q4t	62.46 MB RX, 31.23 MB TX
Cisco Nexus 7000 (M2 series)	24-port 10GE SFP+	8q2t	1p7q4t	5.21 MB RX, 5.21 MB TX
Cisco Nexus 7700 (F3 Series)	12-port 100GE CPAK across 12 ASICs	4q	4q	144 MB shared, VoQ
Cisco Nexus 7700 (F3 Series)	24-port 40GE QSFP+ across 12 ASICs	4q	4q	144 MB shared, VoQ
Cisco Nexus 7700 (F3 Series)	48-port 10GE SFP+ across 6 ASICs	4q	4q	144 MB shared, VoQ

Other Shared Memory Switches

Model	Port Type	RX Queue	Total Buffer	TX Buffer
Catalyst 3550-24	24 10/100-base-T + 2 x 1G GBIC	8Q	2 MB	2 MB
Extreme X450-G2-48T-10G	48 1000-base-T + 4 x 10G SFP+	8Q	4 MB
Extreme 620X-16	16 10-Gbps SFP+	8Q	2 MB	2 MB
Extreme 620X-10	10 10-Gbps SFP+	8Q	2 MB	2 MB
Brocade FCX624S	24Gig-E and 4 SFP+	8Q	2 MB	1.04 MB to 1 port
Juniper Ex4300	48 or 24 Tw-pair, 20 SFP+	8Q		undisclosed
Juniper Ex4500 / Ex4550	40 SFP+ plus 8 SFP+	8Q	4 MB per ASIC	230 KB
Brocade ICX6610-24	24Gig-E w 8 SFP+	8Q	4 MB	1 MB to 1 port
HP 3800	24Gig-E and 4 10Gb/s	8Q		0.23 MB
HP 2920-24	24 tw-pr Gig-E and 4 optional 10Gb/s	8Q	11.25 MB	6.75 MB shared TX
HP 2824	20 tw-pr Gig-E and 4 SFP	4Q	0.512 MB shared	0.512 MB shared
HP A5800-24G	24Gig-E and 4 10Gb/s	8Q	4 MB	4 MB
HP E6600-24G-4XG	24Gig-E w 2 10Gb/s	8Q	18 MB for GE	18 MB
Arista 7124SX	24 x SFP+	8Q	2 MB/sw-chip	1.238 + 0.02 MB
Arista 7148SX	48 SFP+	8Q	2 MB/sw-chip, 8 MB total	1.238 + 0.02 MB
Arista DCS-7150S-24	24 SFP+	8Q	7.5 MB
Arista DSC-7150S-52	52 SFP+	8Q	7.5 MB
Arista DCS-7150S-64	48 SFP+ and 4 QSFP+	8Q	7.5 MB
Dell 8024	24 SFP+	2Q	2 MB
Dell 6248	48 Gig-E, 4 x SFP+	8Q	0.75 MB	98 KB per port
Dell 7024	24 Gig-E, 4 x SFP+	8Q	4 MB	4 MB
IBM BNT G8052	48 GE + 4 SFP+	8Q	4 MB/switch	4 MB
Nortel 5520-48T ver 1-3	48 GE + 4 SFP shared	8Q	786 KB per 12-port	131 KB w 8 Queues
Nortel 5520-48T ver 4-5	48 GE + 4 SFP shared	1-8Q	786 KB per 12-port	786 KB w 1 Queue
Catalyst 3750G-48TS, 2960G	12 ASICs w/ 4 GE ports ea	8Q	576KB per ASIC	384 KB per ASIC
Catalyst 2960S	Single ASIC: 48 +2 10Gb/s	8Q	2 MB	2 MB
Catalyst 3750E, 3560E, 3750X & 3560X	ASIC support 24 GE ports or 2 x 10G	2Q	2750KB per ASIC	2 MB per ASIC
Catalyst 2960-X	ASIC support 48 GE ports AND uplink and stack	4Q		4 MB per ASIC
Catalyst 4948E	48 GigE + 4 SFP+	4	17.5 MB	Max 16 MB to 1 port
Cisco Catalyst 4510R+E	Chassis w 8 interface slots – 12 port SFP+ line card	8	32 MB on Supervisor	Max 14 MB to 1 port
Cisco Catalyst WS-C4500X-32SFP+	1 RU w 32 SFP+ ports and module for 8 more	8	32 MB
Cisco Nexus 3548 and 3548X	48 SFP+	4	18 MB	5.8 MB

Huawei

Model	Port Type	TX Buffer
Huawei S6720-54C-EI-48S	48 SFP+ and 2 QSFP and 4 QSFP expansion	8 MB to 1 port
Huawei S6720-30C-EI-24S	24 SFP+ and 2 QSFP and 4 QSFP expansion	8 MB to 1 port