The numbers are for popular compilers. The actual sizes will vary according to the compiler and optimization used. Ethernet code sizes and RAM usage will vary depending upon the ethernet controller used, onboard or external.

8051 Processor
CMX-MicroNet v3.09c
Keil 8051 v8.08 tools, optimization level 9, size

Code Sizes (bytes)
UDP/IP (no TCP) + core	9337
TCP/IP (no UDP) + core	14,426
UDP/TCP/IP + core	15,971
(Please note that UDP/IP and TCP/IP are usually mutually exclusive)
IP Fragmentation	4461
PPP	7854
Modem	799
HTTP server	6329
Virtual File System	1481
Ethernet	5215
DHCP client	3058
BOOTP	1262
FTP Server	5694
FTP Client	5919
TFTP Client	1260
SMTP	2686
SNTP	3001
POP3	5890
DNS	1434
IGMP	1848
Utility	1993
SNMP v1 + v2 with default MIBs	4133
SNMP v1 + v2 trap	1335

RAM Sizes (bytes)
UDP/SLIP	161
HTTP	135
Ethernet	82

Without IP Fragmentation: add user selected buffer sizes + 63 bytes per socket

With IP Fragmentation: add user selected buffer sizes + 34 bytes + 83 bytes per socket + size of reassembly buffer(s)

Ethernet throughput numbers are calculated by timing the transmission of 1000 UDP packets containing 1460 bytes of data.

Description	Speed (Mbit/second)
SiLabs C8051Fx20-TB board with C8051F120 processor running at 49 MHz, CP2200 ethernet	2.07
SiLabs C8051Fx20-TB board with C8051F120 processor running at 49 MHz, CS8900a ethernet	2.17